Hello back!
Thanks for your sin.bin example Helped me a lot to not waste time on this part!

Then I succeeded in using GNUplot with the binary datas I generate with my simulation code using

Code:

double buffer[]={x, y, Z(i,j)}; 
fwrite(buffer, sizeof(double), sizeof(buffer), Mesh);

which successfully:
- produce smaller and binary datas
- and permit to make plots with gnuplot using

Code:

gnuplot> plot "Mesh0.dat" binary format='%3lf' using 2:3 w d

But now, the following point is the last: how to select my datas using awk with binary datas ?
With ascii datas, I had to write in gnuplot the line

Code:

gnuplot> plot "< awk '{if($1==0) print }' Mesh0.dat" using 2:3 with dots

But what about filtering binary datas with awk ?

After few hours (!!) of walking around gnu.org awk guide, I some tricks to make conversions
- invoque awk --use-non-decimal-numbers
- use the following script gnu.org/software/gawk/manual/gawk.html#Ordinal-Functions or #Bitwise-Functions [did not posted 5 posts yet, can send full link sorry]

Quite hard! However, everybody use binary data in good simulation codes... How do they manage data filtering ?

When this gonna work, I think I will turn to perl to avoid such mess.
PS: we can use any program under gnuplot using the "<" operator in plot command, then if nothing is possible with binary in awk, we can add a step with "od" or perl. Those stuff are new for me!

Thanks a lot,
Thibault

---------- Post updated at 07:32 PM ---------- Previous update was at 07:27 PM ----------

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