Re: Calling Octave from Python

[Stefan van der Walt]

The problem is that Octave does not close, so that readlines() cannot
return.  Try something like

----
import os, string

[pwrite, pread] = os.popen3("/usr/bin/octave -q")

pwrite.write("x = [1,2,3];\n")
pwrite.write("printf('%f\\n', sum(x));\n")
pwrite.flush()
pwrite.close()

result = pread.readlines()
pread.close()

print ("Sum = %s" % result[0])
----

Regards
Stefan

On Mon, Aug 16, 2004 at 12:43:42PM +1000, Maurice Ling wrote:
> Hi,
> 
> I've been trying to find a way to call Octave from Python and a previous 
> message in this list uses the following codes...
> 
> import os
> import string
> 
> # make sure to call ocatve with the "quiet" flag
> [pwrite, pread] = os.popen2("octave -q","w")
> 
> pwrite.write("x = [1,2,3];\n")
> pwrite.write("printf('%f\\n', sum(x));\n")
> 
> # always flush the output to avoid deadlocks
> pwrite.flush()
> result = pread.readline()
> print ("Sum = %f" % string.atof(result))
> 
> pwrite.close()
> pread.close()
> 
> 
> But python freezes itself after "result = pread.readline()". I'm 
> wondering what is wrong?
> 
> Thanks
> Cheers
> Maurice
> 
> -- 
> Maurice Han Tong LING, BSc(Hons)(MCB), AdvDipComp, SN
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