<html>
  <head>
    <meta content="text/html; charset=ISO-8859-1"
      http-equiv="Content-Type">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    <div class="moz-cite-prefix">Jeff,<br>
      <br>
      Thanks. The second trick works well.<br>
      <br>
      Haibin<br>
      <br>
      On 8/7/2012 12:39 PM, Jeff Duda wrote:<br>
    </div>
    <blockquote
cite="mid:CAAig09B_4y2NRqM7ugj7dPizpJGcwGnVcS=MhidCNUoahy5kqg@mail.gmail.com"
      type="cite">So you want to plot the difference between a given
      variable at time t and the same variable at time t-1 for a range
      of time values?&nbsp; If so, then set your time dimension to encompass
      the entire period, then display:<br>
      <br>
      'd var - var(t-1)'<br>
      <br>
      if Grads gives you any guff over that, try enclosing the
      expression in a tloop() function:<br>
      <br>
      'd tloop(var-var(t-1))'<br>
      <br>
      Jeff Duda<br>
      <br>
      <div class="gmail_quote">On Tue, Aug 7, 2012 at 10:57 AM, Haibin
        Li <span dir="ltr">&lt;<a moz-do-not-send="true"
            href="mailto:hli@envsci.rutgers.edu" target="_blank">hli@envsci.rutgers.edu</a>&gt;</span>
        wrote:<br>
        <blockquote class="gmail_quote" style="margin:0 0 0
          .8ex;border-left:1px #ccc solid;padding-left:1ex">Hello there,<br>
          <br>
          I have a time series for a given geographic location, now I
          want to plot<br>
          a time series map for the delta T, i.e.,<br>
          Var(t=2)-Var(t=1),Var(t=3)-Var(t=2), ...,
          Var(t=end)-Var(t=end-1).<br>
          Does anyone know what command I can use to achieve that
          purpose?<br>
          Thanks.<br>
          <br>
          <br>
          Haibin<br>
          _______________________________________________<br>
          gradsusr mailing list<br>
          <a moz-do-not-send="true" href="mailto:gradsusr@gradsusr.org">gradsusr@gradsusr.org</a><br>
          <a moz-do-not-send="true"
            href="http://gradsusr.org/mailman/listinfo/gradsusr"
            target="_blank">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
        </blockquote>
      </div>
      <br>
      <br clear="all">
      <br>
      -- <br>
      Jeff Duda<br>
      Graduate research assistant<br>
      University of Oklahoma School of Meteorology<br>
      Center for Analysis and Prediction of Storms<br>
      <br>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <br>
      <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>
    </blockquote>
    <br>
  </body>
</html>