[gradsusr] fwrite gridding issue

[Thomas Robinson]

Here is my code that opens and writes out the data:

      open (unit=291,file="chi_33yr.dat", access="direct",
     &      status="unknown",recl=4*nx*ny*nt*files)
          write (291, rec=1) chi

The variable chi has dimensions nx,ny,nt*files .

I added options sequential to the descriptor file and the same thing is
happening.  Here is my descriptor file:

dset ^chi_33yr.dat
title Velocity Potential
options sequential
undef 9.999e+20
xdef 144 linear 0 2.5
ydef 73 linear -90 2.5
zdef 1 levels 200
tdef 48212 linear 00Z01JAN1979 360mn
vars 1
chi 0 x,y,t 1 ** velocity potential
endvars

All of your input is very much appreciated.

-Tom


On Fri, May 11, 2012 at 3:16 AM, Jennifer Adams <jma at cola.iges.org> wrote:

> Tom, Did you include 'options sequential' in your descriptor file for your
> new binary file? --Jennifer
>
>
> On May 10, 2012, at 8:49 AM, Raghu Reddy wrote:
>
> I am not a grads user, just responding to the FORTRAN/C issue.****
> ** **
> If you do a normal sequential FORTRAN write, it writes an end-of-record
> marker at the beginning **and** at the end of **every** write.  Since you
> mentioned that the data is skewed, I assume you wrote all the 48,000 values
> with one write statement, and that would result in one EOR marker at the
> beginning and one EOR marker at the end.****
> ** **
> If you don’t want these EOR markers you could write the file out as direct
> access files in Fortran.****
> ** **
> Hope this helps.****
> ** **
> Thanks,****
> ** **
> --Raghu****
> ** **
> ** **
> ** **
> *From:* gradsusr-bounces at gradsusr.org [mailto:
> gradsusr-bounces at gradsusr.org] *On Behalf Of *Thomas Robinson
> *Sent:* Wednesday, May 09, 2012 11:36 PM
> *To:* GrADS Users Forum
> *Subject:* [gradsusr] fwrite gridding issue****
> ** **
>
> Aloha,
>
> I used fwrite to write out to a binary file in order to create a large
> file with about 48000 time steps for global data (because I am crazy).  I
> noticed that when I use fortran to create a new data file that has all
> 48000, it doesn't match with what the original data plotted, instead it
> seems skewed.  No manipulations were done to the data, it was just read it
> all in and write it out.  When I tried to loop the data, I further noticed
> that the northern border looped around the south and then moved upwards
> back to the north.  It just keeps looping around and it's odd because the
> top boundary of the map isn't continuous with the bottom boundary (unlike
> the side boundaries which are continuous).  Anyways, I am wondering why
> this happened and what I can do to make it work out correctly.
>
> Here is my fwrite code.  it is the first time step, nt is the last time
> step, chi is the velocity potential that was calculated using 'define chi =
> fish_chi(UGRDprs,VGRDprs)' :
> *# set up global domain
> 'set lev 200 '
> 'set lat -90 90'
> 'set lon 0 360'
> *#**************************************************************
> say 'write data out to binary file called CHI.200hPa'filenum'.dat'
> 'set fwrite -le -sq -cl CHI_200hPa_'filenum'.dat'
> 'set gxout fwrite'
> while (it <= nt)
>      'set t 'it
>      'display chi'
> it=it+1
> endwhile
> 'disable fwrite'
>
> Mahalo for your help!
> -Tom
>
> --
> Tom Robinson
> President Graduate Student Organization
> Student Caucus Representative for the Graduate Student Organization
> Graduate Student - Department of Meteorology
> 732-718-2323****
> _______________________________________________
>
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr
>
>
> --
> Jennifer M. Adams
> IGES/COLA
> 4041 Powder Mill Road, Suite 302
> Calverton, MD 20705
> jma at cola.iges.org
>
>
>
>
> _______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr
>
>


-- 
Tom Robinson
President Graduate Student Organization
Student Caucus Representative for the Graduate Student Organization
Graduate Student - Department of Meteorology
732-718-2323
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20120510/e29dc2fa/attachment-0003.html