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    <p>Evgeny,</p>
    <p>Again you are changing your script in between questions.  Please
      just fix one thing at a time.  You have repeated the confusion of
      the variable "t" in this line:</p>
    <p>'define
dewp850mb=(t-273.15)-((14.55+0.114*(t-273.15))*(1-0.01*rh)+pow((2.5+0.007*(t-273.15))*(1-0.01*rh),3)+(15.9+0.117*(t-273.15))*pow((1-0.01*rh),14))'</p>
    <p>I presume by "t" you mean "temperature" and not "time".  This
      won't work since "t" at this point is not defined.</p>
    <p>Second, you need to put all the code within the while loop.  For
      example, you have "printim" presumably to make images for each
      time-step, but since this is outside the while loop, you'll only
      get one.</p>
    <p>Finally, there does not seem to be "rhprs" in this data set, or
      at least it's not being read reliably via OPeNDAP.<br>
    </p>
    <p>Comment out the lines defining rh and dewp850mb, move all the
      stuff below "endwhile" into the "while" loop, and it works, at
      least for me.</p>
    <p>Jim<br>
    </p>
    <div class="moz-cite-prefix">On 5/10/21 7:49 AM, Evgeny Gavrilov
      wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAKh9uO82FRBoXn_bKMpaJiD2GdKpAso-0f=Z3yz=XgroZOsfGA@mail.gmail.com">
      <meta http-equiv="content-type" content="text/html; charset=UTF-8">
      <div dir="ltr">but why? can you explain the reasons? 
        <div><br>
        </div>
        <div>'reinit'<br>
          <br>
          'sdfopen <a
href="https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210510/gfs_0p25_12z"
            moz-do-not-send="true">https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210510/gfs_0p25_12z</a>'<br>
          <br>
          'set lon 30 50'<br>
          'set lat 40 50'<br>
          'set t 1 80'<br>
          <br>
          'define temp=tmpprs(lev=850)'<br>
          'define rh=rhprs(lev=850)'<br>
          'define
dewp850mb=(t-273.15)-((14.55+0.114*(t-273.15))*(1-0.01*rh)+pow((2.5+0.007*(t-273.15))*(1-0.01*rh),3)+(15.9+0.117*(t-273.15))*pow((1-0.01*rh),14))'<br>
          'define
          vapr850mb=6.112*exp((17.67*dewp850mb)/(dewp850mb+243.5))'<br>
          'define e850mb=vapr850mb*1.001+(850-100)/900*0.0034'<br>
          'define w850mb=0.62197*(e850mb/(850-e850mb))'<br>
          'define te850mb=(t+(2260000*w850mb/1004))'<br>
          'define te=(te850mb*pow((1000/850),(287/1004)))-273.15'<br>
          <br>
          maps = 20<br>
          'set display color white'<br>
          i = 1<br>
          while ( i<maps )<br>
            'set t ' i<br>
            'set gxout shaded'<br>
            'd te - te(t='i-1')'<br>
            'cbarn'<br>
            'clear'<br>
            i=i+1<br>
          endwhile<br>
          <br>
          'q dims'<br>
          times = sublin(result,5)<br>
          mse = subwrd(times,6)<br>
          <br>
          'set strsiz 0.17'<br>
          'set string 1 r 6 0' ; 'draw string 4.85 7.98 GFS forecast:
          'mse<br>
          'set string 1 r 6 0' ; 'draw string 10.1 7.98 Run: 'met<br>
          <br>
          'printim C:\Users\123\for\te_'i'.png x800 y650'<br>
          <br>
          'clear'<br>
          <br>
          return<br>
        </div>
      </div>
      <br>
      <div class="gmail_quote">
        <div dir="ltr" class="gmail_attr">On Mon, May 10, 2021 at 8:14
          PM Jeff Duda <<a href="mailto:jeffduda319@gmail.com"
            moz-do-not-send="true">jeffduda319@gmail.com</a>> wrote:<br>
        </div>
        <blockquote class="gmail_quote" style="margin:0px 0px 0px
          0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
          <div dir="ltr">
            <div>Do you see it? That very first error message points to
              the fact that your data file either was not opened
              successfully or  you are not able to access the data
              within it.</div>
            <div><br>
            </div>
            <div>First thing you should do is confirm you can plot basic
              fields from the data file.</div>
            <div><br>
            </div>
            <div>Jeff<br>
            </div>
          </div>
          <br>
          <div class="gmail_quote">
            <div dir="ltr" class="gmail_attr">On Mon, May 10, 2021 at
              10:05 AM Evgeny Gavrilov <<a
                href="mailto:eugen420@gmail.com" target="_blank"
                moz-do-not-send="true">eugen420@gmail.com</a>> wrote:<br>
            </div>
            <blockquote class="gmail_quote" style="margin:0px 0px 0px
              0.8ex;border-left:1px solid
              rgb(204,204,204);padding-left:1ex">
              <div dir="ltr"><img
                  src="cid:part4.B2708D00.3C34F062@hawaii.edu"
                  alt="778.png" class="" width="474" height="378"><br>
              </div>
              <br>
              <div class="gmail_quote">
                <div dir="ltr" class="gmail_attr">On Mon, May 10, 2021
                  at 6:31 PM Jeff Duda <<a
                    href="mailto:jeffduda319@gmail.com" target="_blank"
                    moz-do-not-send="true">jeffduda319@gmail.com</a>>
                  wrote:<br>
                </div>
                <blockquote class="gmail_quote" style="margin:0px 0px
                  0px 0.8ex;border-left:1px solid
                  rgb(204,204,204);padding-left:1ex">
                  <div dir="ltr">
                    <div>at least one of your variables or function
                      calls above is wrong based on the error messages.
                      However, because GrADS throws out more messages
                      than the window you showed can contain, I can't
                      see the first error message, which is likely the
                      most important one. Show us that message.</div>
                    <div><br>
                    </div>
                    <div>Jeff Duda<br>
                    </div>
                  </div>
                  <br>
                  <div class="gmail_quote">
                    <div dir="ltr" class="gmail_attr">On Mon, May 10,
                      2021 at 3:13 AM Evgeny Gavrilov <<a
                        href="mailto:eugen420@gmail.com" target="_blank"
                        moz-do-not-send="true">eugen420@gmail.com</a>>
                      wrote:<br>
                    </div>
                    <blockquote class="gmail_quote" style="margin:0px
                      0px 0px 0.8ex;border-left:1px solid
                      rgb(204,204,204);padding-left:1ex">
                      <div dir="ltr">  the map is not drawn again
                        <div><br>
                        </div>
                        <div><a
                            href="https://www.youtube.com/watch?v=s8JG6BUVh8c"
                            target="_blank" moz-do-not-send="true">https://www.youtube.com/watch?v=s8JG6BUVh8c</a>
                          <div style="outline:currentcolor none
                            medium;padding:10px
                            0px;width:22px;margin:2px 0px 0px"><br>
                          </div>
                        </div>
                      </div>
                      <br>
                      <div class="gmail_quote">
                        <div dir="ltr" class="gmail_attr">On Mon, May
                          10, 2021 at 4:57 AM James Potemra <<a
                            href="mailto:jimp@hawaii.edu"
                            target="_blank" moz-do-not-send="true">jimp@hawaii.edu</a>>
                          wrote:<br>
                        </div>
                        <blockquote class="gmail_quote"
                          style="margin:0px 0px 0px
                          0.8ex;border-left:1px solid
                          rgb(204,204,204);padding-left:1ex">
                          <div>
                            <p>Evgeny,</p>
                            <p>You have a lot of curiosities in your
                              script.  First, it's never a good to mix
                              GrADS variables (e.g., "t") with your own:</p>
                            <p>'set t 1 20'<br>
                              'define t=tmpprs(lev=850)'</p>
                            <p>instead of 'define t=' maybe make this
                              'define temp=' or something like that. 
                              Second, you have <br>
                            </p>
                            <p>'define a = thetae'</p>
                            <p>but thetae is not defined anywhere. 
                              Third, no need set time range every time
                              you define the variables; set it once. 
                              Finally, as Jeff suggested a while back,
                              you'll need to add quotes to get the time
                              index as a number:</p>
                            <p>'d a - a(t-1)' --> 'd a - a(t='i-1')</p>
                            <p>---------------------------</p>
                            <p>* set URL for data<br>
                              'sdfopen <a
href="https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210509/gfs_0p25_12z"
                                target="_blank" moz-do-not-send="true">https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210509/gfs_0p25_12z</a>'<br>
                              <br>
                              * define lat/lon/time ranges<br>
                              'set lon 30 50'<br>
                              'set lat 40 50'<br>
                              'set t 1 81'<br>
                              <br>
                              * define variables<br>
                              'define temp=tmpprs(lev=850)'<br>
                              'define rh=rhprs(lev=850)'<br>
                              'define
dewp850mb=(t-273.15)-((14.55+0.114*(t-273.15))*(1-0.01*rh)+pow((2.5+0.007*(t-273.15))*(1-0.01*rh),3)+(15.9+0.117*(t-273.15))*pow((1-0.01*rh),14))'<br>
                              'define
                              vapr850mb=6.112*exp((17.67*dewp850mb)/(dewp850mb+243.5))'<br>
                              'define
                              e850mb=vapr850mb*1.001+(850-100)/900*0.0034'<br>
                              'define
                              w850mb=0.62197*(e850mb/(850-e850mb))'<br>
                              'define te850mb=(t+(2260000*w850mb/1004))'<br>
                              'define
                              epa=(te850mb*pow((1000/850),(287/1004)))-273.16'<br>
                              <br>
                            </p>
                            * draw maps<br>
                            maps = 20<br>
                            'set display color white'<br>
                            i = 1<br>
                            while ( i<maps )<br>
                              'set t ' i<br>
                              'set gxout shaded'<br>
                            * I have not idea what you want to do, but
                            this will display the difference between the
                            current timestep and the one prior  <br>
                              'd temp - temp(t='i-1')'<br>
                              'cbarn'<br>
                              'clear'<br>
                              i=i+1<br>
                            endwhile
                            <p>-------------------------<br>
                            </p>
                            <p><br>
                            </p>
                            <div>On 5/9/21 9:02 AM, Evgeny Gavrilov
                              wrote:<br>
                            </div>
                            <blockquote type="cite">
                              <div dir="ltr">All the same. The maps are
                                not drawn 
                                <div><br>
                                </div>
                                <div>You can run my script: </div>
                                <div><br>
                                </div>
                                <div>'reinit'</div>
                                <div><br>
                                </div>
                                'sdfopen <a
href="https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210509/gfs_0p25_12z"
                                  target="_blank" moz-do-not-send="true">https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210509/gfs_0p25_12z</a>'<br>
                                <br>
                                'set lon 30 50'<br>
                                'set lat 40 50'<br>
                                <br>
                                'set display color white'<br>
                                <br>
                                maps = 20<br>
                                  i = 1<br>
                                  while ( i<maps )<br>
                                'set t ' i<br>
                                <br>
                                'set t 1 20'<br>
                                'define t=tmpprs(lev=850)'
                                <div>'set t 1 20'  <br>
                                  'define rh=rhprs(lev=850)'<br>
                                  'set t 1 20'  <br>
                                  'define
dewp850mb=(t-273.15)-((14.55+0.114*(t-273.15))*(1-0.01*rh)+pow((2.5+0.007*(t-273.15))*(1-0.01*rh),3)+(15.9+0.117*(t-273.15))*pow((1-0.01*rh),14))'<br>
                                  'set t 1 20'  <br>
                                  'define
                                  vapr850mb=6.112*exp((17.67*dewp850mb)/(dewp850mb+243.5))'<br>
                                  'set t 1 20'  <br>
                                  'define
                                  e850mb=vapr850mb*1.001+(850-100)/900*0.0034'<br>
                                  'set t 1 20'  <br>
                                  'define
                                  w850mb=0.62197*(e850mb/(850-e850mb))'<br>
                                  'set t 1 20'  <br>
                                  'define
                                  te850mb=(t+(2260000*w850mb/1004))'<br>
                                  'set t 1 20'<br>
                                  'define
                                  epa=(te850mb*pow((1000/850),(287/1004)))-273.16'<br>
                                  <br>
                                  'set gxout shaded'
                                  <div>'define a = thetae'
                                    <div>'d a - a(t-1)'<br>
                                      'cbarm'<br>
                                      <br>
                                      'printim
                                      C:\Users\123\for\temp_'i'.png x800
                                      y600'<br>
                                      <br>
                                      'clear'<br>
                                      <br>
                                      i=i+1<br>
                                      endwhile<br>
                                      <br>
                                      <div>return  <br>
                                      </div>
                                    </div>
                                  </div>
                                </div>
                              </div>
                              <br>
                              <div class="gmail_quote">
                                <div dir="ltr" class="gmail_attr">On
                                  Sun, May 9, 2021 at 8:54 PM Jeff Duda
                                  <<a
                                    href="mailto:jeffduda319@gmail.com"
                                    target="_blank"
                                    moz-do-not-send="true">jeffduda319@gmail.com</a>>
                                  wrote:<br>
                                </div>
                                <blockquote class="gmail_quote"
                                  style="margin:0px 0px 0px
                                  0.8ex;border-left:1px solid
                                  rgb(204,204,204);padding-left:1ex">
                                  <div dir="ltr">
                                    <div>Oh, yeah...I missed that. Good
                                      catch, James!</div>
                                    <div><br>
                                    </div>
                                    <div>But the display command I
                                      suggested to him (d a - a(t-1))
                                      certainly is valid for plotting
                                      the 1-time-step change in thetae,
                                      which I presume is what he wanted
                                      originally. It depends on the
                                      final graphic type he is trying to
                                      produce.<br>
                                    </div>
                                  </div>
                                  <br>
                                  <div class="gmail_quote">
                                    <div dir="ltr" class="gmail_attr">On
                                      Sun, May 9, 2021 at 10:41 AM James
                                      Potemra <<a
                                        href="mailto:jimp@hawaii.edu"
                                        target="_blank"
                                        moz-do-not-send="true">jimp@hawaii.edu</a>>
                                      wrote:<br>
                                    </div>
                                    <blockquote class="gmail_quote"
                                      style="margin:0px 0px 0px
                                      0.8ex;border-left:1px solid
                                      rgb(204,204,204);padding-left:1ex">
                                      <div>
                                        <p>You are not defining the time
                                          correctly.  In this new script
                                          you define "thetae", and this
                                          is still only defined for a
                                          single time-step.  You need to
                                          put the "set t 1 81" before
                                          any variable you want to be a
                                          function of time.  Also, your
                                          statement "d a-a(t-1)" doesn't
                                          make sense since "a" (if
                                          defined properly) will be a
                                          function of time/lat/lon.  If
                                          you want to plot 81 contour
                                          plots, each one as a different
                                          between current time and time
                                          before, you'll have to script
                                          that like you did in your
                                          first example.</p>
                                        <p>Jim<span
                                            style="color:rgb(80,0,80)"><br>
                                          </span></p>
                                        <div>On 5/8/21 12:52 PM, Evgeny
                                          Gavrilov wrote:<br>
                                        </div>
                                        <blockquote type="cite">
                                          <div dir="ltr">this command:
                                            'set t 1 81' before 'define'
                                            does not solve this problem<br>
                                          </div>
                                          <br>
                                          <div class="gmail_quote">
                                            <div dir="ltr"
                                              class="gmail_attr">On Sun,
                                              May 9, 2021 at 1:11 AM
                                              Jeff Duda <<a
                                                href="mailto:jeffduda319@gmail.com"
                                                target="_blank"
                                                moz-do-not-send="true">jeffduda319@gmail.com</a>>
                                              wrote:<br>
                                            </div>
                                            <blockquote
                                              class="gmail_quote"
                                              style="margin:0px 0px 0px
                                              0.8ex;border-left:1px
                                              solid
                                              rgb(204,204,204);padding-left:1ex">
                                              <div dir="ltr">
                                                <div>What do you mean by
                                                  "doesn't help"? We
                                                  need specifics to be
                                                  able to fully help
                                                  you.</div>
                                                <div><br>
                                                </div>
                                                <div>Jeff Duda<br>
                                                </div>
                                              </div>
                                              <br>
                                              <div class="gmail_quote">
                                                <div dir="ltr"
                                                  class="gmail_attr">On
                                                  Sat, May 8, 2021 at
                                                  1:53 PM Evgeny
                                                  Gavrilov <<a
                                                    href="mailto:eugen420@gmail.com"
                                                    target="_blank"
                                                    moz-do-not-send="true">eugen420@gmail.com</a>>
                                                  wrote:<br>
                                                </div>
                                                <blockquote
                                                  class="gmail_quote"
                                                  style="margin:0px 0px
                                                  0px
                                                  0.8ex;border-left:1px
                                                  solid
                                                  rgb(204,204,204);padding-left:1ex">
                                                  <div dir="ltr">  still
                                                    doesn't help 'set t
                                                    1 81' 
                                                    <div><br>
                                                    </div>
                                                    <div><span
                                                        style="color:rgb(80,0,80)">'reinit'<br>
                                                        <br>
                                                        'sdfopen <a
href="https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210508/gfs_0p25_12z"
target="_blank" moz-do-not-send="true">https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210508/gfs_0p25_12z</a>'<br>
                                                        <br>
                                                        'set mpdset
                                                        hires'<br>
                                                        'set lon 10 30'<br>
                                                        'set lat 40 50'<br>
                                                        <br>
                                                        'set display
                                                        color white'<br>
                                                        <br>
                                                        'set gxout
                                                        shaded'<br>
                                                      </span>'define tc
                                                      = tmpprs(lev=850)'<br>
                                                      'define rh =
                                                      rhprs(lev=850)'<br>
                                                      'define dewp850mb
                                                      =
(tc-273.15)-((14.55+0.114*(tc-273.15))*(1-0.01*rh)+pow((2.5+0.007*(tc-273.15))*(1-0.01*rh),3)+(15.9+0.117*(tc-273.15))*pow((1-0.01*rh),14))'<br>
                                                      'define vapr850mb
                                                      =
                                                      6.112*exp((17.67*dewp850mb)/(dewp850mb+243.5))'<br>
                                                      'define e850mb =
                                                      vapr850mb*1.001+(850-100)/900*0.0034'<br>
                                                      'define w850mb =
                                                      0.62197*(e850mb/(850-e850mb))'<br>
                                                      'define te850mb =
(tc+(2260000*w850mb/1004))'<br>
                                                      'define thetae =
                                                      (te850mb*pow((1000/850),(287/1004)))-273.16'<br>
                                                      <br>
                                                      'set t 1 81'<br>
                                                      'define a =
                                                      thetae'<span
                                                        style="color:rgb(80,0,80)"><br>
                                                        'd a-a(t-1)'<br>
                                                        'cbarm'<br>
                                                        <br>
                                                        'printim
                                                        C:\Users\for\temp.png
                                                        x800 y600'<br>
                                                        <br>
                                                        'clear'<br>
                                                        <br>
                                                        return</span></div>
                                                  </div>
                                                  <br>
                                                  <div
                                                    class="gmail_quote">
                                                    <div dir="ltr"
                                                      class="gmail_attr">On
                                                      Sat, May 8, 2021
                                                      at 11:15 PM Evgeny
                                                      Gavrilov <<a
                                                        href="mailto:eugen420@gmail.com"
                                                        target="_blank"
moz-do-not-send="true">eugen420@gmail.com</a>> wrote:<br>
                                                    </div>
                                                    <blockquote
                                                      class="gmail_quote"
                                                      style="margin:0px
                                                      0px 0px
                                                      0.8ex;border-left:1px
                                                      solid
                                                      rgb(204,204,204);padding-left:1ex">
                                                      <div dir="ltr">still
                                                        doesn't help
                                                        'set t 1 81' 
                                                        <div><br>
                                                        </div>
                                                        <div>'reinit'<br>
                                                          <br>
                                                          'sdfopen <a
href="https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210508/gfs_0p25_12z"
target="_blank" moz-do-not-send="true">https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210508/gfs_0p25_12z</a>'<br>
                                                          <br>
                                                          'set mpdset
                                                          hires'<br>
                                                          'set lon 10
                                                          30'<br>
                                                          'set lat 40
                                                          50'<br>
                                                          <br>
                                                          'set display
                                                          color white'<br>
                                                          <br>
                                                          'set gxout
                                                          shaded'<br>
                                                          'define tc =
                                                          tmpprs(lev=850)'<br>
                                                          'define rh =
                                                          rhprs(lev=850)'<br>
                                                          'define
                                                          dewp850mb =
(tc-273.15)-((14.55+0.114*(tc-273.15))*(1-0.01*rh)+pow((2.5+0.007*(tc-273.15))*(1-0.01*rh),3)+(15.9+0.117*(tc-273.15))*pow((1-0.01*rh),14))'<br>
                                                          'define
                                                          vapr850mb =
                                                          6.112*exp((17.67*dewp850mb)/(dewp850mb+243.5))'<br>
                                                          'define e850mb
                                                          =
                                                          vapr850mb*1.001+(850-100)/900*0.0034'<br>
                                                          'define w850mb
                                                          =
                                                          0.62197*(e850mb/(850-e850mb))'<br>
                                                          'define
                                                          te850mb =
                                                          (tc+(2260000*w850mb/1004))'<br>
                                                          'define thetae
                                                          =
                                                          (te850mb*pow((1000/850),(287/1004)))-273.16'<br>
                                                          <br>
                                                          'set t 1 81'<br>
                                                          'define a =
                                                          thetae'<br>
                                                          'd a-a(t-1)'<br>
                                                          'cbarm'<br>
                                                          <br>
                                                          'printim
                                                          C:\Users\for\temp.png
                                                          x800 y600'<br>
                                                          <br>
                                                          'clear'<br>
                                                          <br>
                                                          return<br>
                                                        </div>
                                                      </div>
                                                      <br>
                                                      <div
                                                        class="gmail_quote">
                                                        <div dir="ltr"
                                                          class="gmail_attr">On
                                                          Sat, May 8,
                                                          2021 at 10:54
                                                          PM James T.
                                                          Potemra <<a
href="mailto:jimp@hawaii.edu" target="_blank" moz-do-not-send="true">jimp@hawaii.edu</a>>
                                                          wrote:<br>
                                                        </div>
                                                        <blockquote
                                                          class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid
                                                          rgb(204,204,204);padding-left:1ex">
                                                          <div>
                                                          <p>You will
                                                          have to set
                                                          the time range
                                                          before
                                                          defining
                                                          variable 'a',
                                                          otherwise it
                                                          will only be
                                                          defined for a
                                                          single time
                                                          step.  Try add
                                                          'set t 1 81'
                                                          before
                                                          defining 'a'.</p>
                                                          <p>Jim<br>
                                                          </p>
                                                          <div>On 5/8/21
                                                          8:42 AM,
                                                          Evgeny
                                                          Gavrilov
                                                          wrote:<br>
                                                          </div>
                                                          <blockquote
                                                          type="cite">
                                                          <div dir="ltr">"i"
                                                          from while.
                                                          <div><br>
                                                          </div>
                                                          <div>maps = 20<br>
                                                            i = 1<br>
                                                            while (
                                                          i<maps )<br>
                                                          'set t ' i <br>
                                                          </div>
                                                          <div><br>
                                                          </div>
                                                          <div>2)
                                                          a-a(t=1) also
                                                          has a report
                                                          about constant
                                                          field
                                                          (value=0) </div>
                                                          <div><br>
                                                          </div>
                                                          <div>'reinit'<br>
                                                          <br>
                                                          'sdfopen <a
href="https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210508/gfs_0p25_12z"
target="_blank" moz-do-not-send="true">https://nomads.ncep.noaa.gov/dods/gfs_0p25/gfs20210508/gfs_0p25_12z</a>'<br>
                                                          <br>
                                                          'set mpdset
                                                          hires'<br>
                                                          'set lon 10
                                                          30'<br>
                                                          'set lat 40
                                                          50'<br>
                                                          <br>
                                                          'set display
                                                          color white'<br>
                                                          <br>
                                                          'set gxout
                                                          shaded'<br>
                                                          'define a =
                                                          tmp2m'<br>
                                                          'd a-a(t-1)'<br>
                                                          'cbarm'<br>
                                                          <br>
                                                          'printim
                                                          C:\Users\for\temp.png
                                                          x800 y600'<br>
                                                          <br>
                                                          'clear'<br>
                                                          <br>
                                                          return<br>
                                                          </div>
                                                          </div>
                                                          <br>
                                                          <div
                                                          class="gmail_quote">
                                                          <div dir="ltr"
class="gmail_attr">On Sat, May 8, 2021 at 10:11 PM Jeff Duda <<a
                                                          href="mailto:jeffduda319@gmail.com"
target="_blank" moz-do-not-send="true">jeffduda319@gmail.com</a>>
                                                          wrote:<br>
                                                          </div>
                                                          <blockquote
                                                          class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid
                                                          rgb(204,204,204);padding-left:1ex">
                                                          <div dir="ltr">
                                                          <div>1a) How
                                                          is 'i' set?</div>
                                                          <div>1b) I
                                                          don't think
                                                          the grads
                                                          scripting
                                                          language
                                                          supports math
                                                          in a command
                                                          line command
                                                          like that.
                                                          You'd have to
                                                          do something
                                                          like</div>
                                                          <div>i = 1</div>
                                                          <div>i2 = i-1</div>
                                                          <div>'d
                                                          a(t='i') -
                                                          a(t='i2')'</div>
                                                          <div><br>
                                                          </div>
                                                          <div>2) This
                                                          command is
                                                          equivalent and
                                                          does not
                                                          require a
                                                          script
                                                          variable
                                                          (provided your
                                                          dimension
                                                          environment is
                                                          set
                                                          appropriately):
                                                          'd a - a(t-1)'</div>
                                                          <div><br>
                                                          </div>
                                                          <div>Jeff Duda<br>
                                                          </div>
                                                          </div>
                                                          <br>
                                                          <div
                                                          class="gmail_quote">
                                                          <div dir="ltr"
class="gmail_attr">On Sat, May 8, 2021 at 12:01 PM Evgeny Gavrilov <<a
href="mailto:eugen420@gmail.com" target="_blank" moz-do-not-send="true">eugen420@gmail.com</a>>
                                                          wrote:<br>
                                                          </div>
                                                          <blockquote
                                                          class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid
                                                          rgb(204,204,204);padding-left:1ex">
                                                          <div dir="ltr">why
                                                          this method
                                                          does not
                                                          working? <br>
                                                          <div><br>
                                                          </div>
                                                          <div>'set
                                                          gxout shaded'<br>
                                                          'define
                                                          a=tmp2m'<br>
                                                          'd a(t='i') -
                                                          a(t='i-1')' <br>
                                                          </div>
                                                          <div><br>
                                                          </div>
                                                          <div>report:
                                                          constant
                                                          field. value =
                                                          0 </div>
                                                          </div>
_______________________________________________<br>
                                                          gradsusr
                                                          mailing list<br>
                                                          <a
                                                          href="mailto:gradsusr@gradsusr.org"
target="_blank" moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
                                                          <a
                                                          href="http://gradsusr.org/mailman/listinfo/gradsusr"
rel="noreferrer" target="_blank" moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                                                          </blockquote>
                                                          </div>
                                                          <br
                                                          clear="all">
                                                          <br>
                                                          -- <br>
                                                          <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div>
                                                          <div dir="ltr">
                                                          <div>
                                                          <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div dir="ltr"><font
                                                          size="2"><span>Jeff
                                                          Duda, Research
                                                          Scientist</span></font></div>
                                                          <div dir="ltr"><font
                                                          size="2"><span></span></font>University
                                                          of Colorado
                                                          Boulder</div>
                                                          <div dir="ltr"><font
                                                          size="2"><span></span></font>Cooperative
                                                          Institute for
                                                          Research in
                                                          Environmental
                                                          Sciences</div>
                                                          <div dir="ltr">NOAA/OAR/ESRL/Global
                                                          Systems
                                                          Laboratory<br>
                                                          <font size="2"><span>
                                                          <span>Boulder,
                                                          CO<br>
                                                          </span></span></font>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
_______________________________________________<br>
                                                          gradsusr
                                                          mailing list<br>
                                                          <a
                                                          href="mailto:gradsusr@gradsusr.org"
target="_blank" moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
                                                          <a
                                                          href="http://gradsusr.org/mailman/listinfo/gradsusr"
rel="noreferrer" target="_blank" moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                                                          </blockquote>
                                                          </div>
                                                          <br>
                                                          <fieldset></fieldset>
                                                          <pre>_______________________________________________
gradsusr mailing list
<a href="mailto:gradsusr@gradsusr.org" target="_blank" moz-do-not-send="true">gradsusr@gradsusr.org</a>
<a href="http://gradsusr.org/mailman/listinfo/gradsusr" target="_blank" moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a>
</pre>
                                                          </blockquote>
                                                          </div>
                                                        </blockquote>
                                                      </div>
                                                    </blockquote>
                                                  </div>
_______________________________________________<br>
                                                  gradsusr mailing list<br>
                                                  <a
                                                    href="mailto:gradsusr@gradsusr.org"
                                                    target="_blank"
                                                    moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
                                                  <a
                                                    href="http://gradsusr.org/mailman/listinfo/gradsusr"
                                                    rel="noreferrer"
                                                    target="_blank"
                                                    moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                                                </blockquote>
                                              </div>
                                              <br clear="all">
                                              <br>
                                              -- <br>
                                              <div dir="ltr">
                                                <div dir="ltr">
                                                  <div>
                                                    <div dir="ltr">
                                                      <div>
                                                        <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div dir="ltr">
                                                          <div dir="ltr"><font
                                                          size="2"><span>Jeff
                                                          Duda, Research
                                                          Scientist</span></font></div>
                                                          <div dir="ltr"><font
                                                          size="2"><span></span></font>University
                                                          of Colorado
                                                          Boulder</div>
                                                          <div dir="ltr"><font
                                                          size="2"><span></span></font>Cooperative
                                                          Institute for
                                                          Research in
                                                          Environmental
                                                          Sciences</div>
                                                          <div dir="ltr">NOAA/OAR/ESRL/Global
                                                          Systems
                                                          Laboratory<br>
                                                          <font size="2"><span>
                                                          <span>Boulder,
                                                          CO<br>
                                                          </span></span></font>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          </div>
                                                        </div>
                                                      </div>
                                                    </div>
                                                  </div>
                                                </div>
                                              </div>
_______________________________________________<br>
                                              gradsusr mailing list<br>
                                              <a
                                                href="mailto:gradsusr@gradsusr.org"
                                                target="_blank"
                                                moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
                                              <a
                                                href="http://gradsusr.org/mailman/listinfo/gradsusr"
                                                rel="noreferrer"
                                                target="_blank"
                                                moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                                            </blockquote>
                                          </div>
                                          <br>
                                          <fieldset></fieldset>
                                          <pre>_______________________________________________
gradsusr mailing list
<a href="mailto:gradsusr@gradsusr.org" target="_blank" moz-do-not-send="true">gradsusr@gradsusr.org</a>
<a href="http://gradsusr.org/mailman/listinfo/gradsusr" target="_blank" moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a>
</pre>
                                        </blockquote>
                                      </div>
_______________________________________________<br>
                                      gradsusr mailing list<br>
                                      <a
                                        href="mailto:gradsusr@gradsusr.org"
                                        target="_blank"
                                        moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
                                      <a
                                        href="http://gradsusr.org/mailman/listinfo/gradsusr"
                                        rel="noreferrer" target="_blank"
                                        moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                                    </blockquote>
                                  </div>
                                  <br clear="all">
                                  <br>
                                  -- <br>
                                  <div dir="ltr">
                                    <div dir="ltr">
                                      <div>
                                        <div dir="ltr">
                                          <div>
                                            <div dir="ltr">
                                              <div dir="ltr">
                                                <div dir="ltr">
                                                  <div dir="ltr">
                                                    <div dir="ltr"><font
                                                        size="2"><span>Jeff
                                                          Duda, Research
                                                          Scientist</span></font></div>
                                                    <div dir="ltr"><font
                                                        size="2"><span></span></font>University
                                                      of Colorado
                                                      Boulder</div>
                                                    <div dir="ltr"><font
                                                        size="2"><span></span></font>Cooperative
                                                      Institute for
                                                      Research in
                                                      Environmental
                                                      Sciences</div>
                                                    <div dir="ltr">NOAA/OAR/ESRL/Global
                                                      Systems Laboratory<br>
                                                      <font size="2"><span>
                                                          <span>Boulder,
                                                          CO<br>
                                                          </span></span></font>
                                                    </div>
                                                  </div>
                                                </div>
                                              </div>
                                            </div>
                                          </div>
                                        </div>
                                      </div>
                                    </div>
                                  </div>
                                </blockquote>
                              </div>
                              <br>
                              <fieldset></fieldset>
                              <pre>_______________________________________________
gradsusr mailing list
<a href="mailto:gradsusr@gradsusr.org" target="_blank" moz-do-not-send="true">gradsusr@gradsusr.org</a>
<a href="http://gradsusr.org/mailman/listinfo/gradsusr" target="_blank" moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a>
</pre>
                            </blockquote>
                          </div>
                        </blockquote>
                      </div>
                      _______________________________________________<br>
                      gradsusr mailing list<br>
                      <a href="mailto:gradsusr@gradsusr.org"
                        target="_blank" moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
                      <a
                        href="http://gradsusr.org/mailman/listinfo/gradsusr"
                        rel="noreferrer" target="_blank"
                        moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                    </blockquote>
                  </div>
                  <br clear="all">
                  <br>
                  -- <br>
                  <div dir="ltr">
                    <div dir="ltr">
                      <div>
                        <div dir="ltr">
                          <div>
                            <div dir="ltr">
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                                    <div dir="ltr"><font size="2"><span>Jeff
                                          Duda, Research Scientist</span></font></div>
                                    <div dir="ltr"><font size="2"><span></span></font>University
                                      of Colorado Boulder</div>
                                    <div dir="ltr"><font size="2"><span></span></font>Cooperative
                                      Institute for Research in
                                      Environmental Sciences</div>
                                    <div dir="ltr">NOAA/OAR/ESRL/Global
                                      Systems Laboratory<br>
                                      <font size="2"><span>
                                          <span>Boulder, CO<br>
                                          </span></span></font>
                                    </div>
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                        </div>
                      </div>
                    </div>
                  </div>
                  _______________________________________________<br>
                  gradsusr mailing list<br>
                  <a href="mailto:gradsusr@gradsusr.org" target="_blank"
                    moz-do-not-send="true">gradsusr@gradsusr.org</a><br>
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                    rel="noreferrer" target="_blank"
                    moz-do-not-send="true">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
                </blockquote>
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                          <div dir="ltr">
                            <div dir="ltr"><font size="2"><span>Jeff
                                  Duda, Research Scientist</span></font></div>
                            <div dir="ltr"><font size="2"><span></span></font>University
                              of Colorado Boulder</div>
                            <div dir="ltr"><font size="2"><span></span></font>Cooperative
                              Institute for Research in Environmental
                              Sciences</div>
                            <div dir="ltr">NOAA/OAR/ESRL/Global Systems
                              Laboratory<br>
                              <font size="2"><span>
                                  <span>Boulder, CO<br>
                                  </span></span></font>
                            </div>
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      <pre class="moz-quote-pre" wrap="">_______________________________________________
gradsusr mailing list
<a class="moz-txt-link-abbreviated" href="mailto:gradsusr@gradsusr.org">gradsusr@gradsusr.org</a>
<a class="moz-txt-link-freetext" href="http://gradsusr.org/mailman/listinfo/gradsusr">http://gradsusr.org/mailman/listinfo/gradsusr</a>
</pre>
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