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Reading Numerical Binary Data using KSH

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# 1  
Old 10-08-2008
Reading Numerical Binary Data using KSH
Hi,

I've searched and couldn't find anyone else with this problem. Is there anyway (preferably using ksh - but other script languages would do) that I can read in binary float data into a text file. The data (arrays from various stages of radar processing) comes in various formats, but mainly its float32, though there are some float complex arrays as well. The ability to switch between big and little endian would be useful too.

This sort of thing is easy in IDL and matlab etc, but thats not a cheap solution.

Any ideas?

Jon
# 2  
Old 10-08-2008
Perl. "man perlfunc" and search for "pack" and "unpack". It's quite cryptic, so I'll refer you also to ...
The first has some examples for doing exactly what you want. Ultimately, you can create command-line perl scripts...

In reading binary data, the other problem you'll encounter is trying to figure out how to get it into Perl. This is not hard, but it's not obvious. As long as your datafile will easily fit in memory, this is suitable. Otherwise, you'll want to read several bytes at a time with sysread(). (Again, see man perlfunc).

Code:
perl -e 'undef $/; $dat=<>; print length($dat),"\n"; ' inputfile.binary

That reads in your binary file and prints out its size. $dat contains the entire image so now you can do manipulations on it with pack/unpack.
Last edited by otheus; 10-08-2008 at 01:12 PM.. Reason: Fixed post per drl
# 3  
Old 10-08-2008
Hi.

Likely otheus meant undef not under:
Code:
perl -e 'undef $/; $dat=<>; print length($dat),"\n"; ' inputfile.binary

... cheers, drl
# 4  
Old 10-08-2008
Cheers guys, I'll have a play with perl.
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