Converting Octave vector to Sage list

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For completeness:

In general, you should be able to access variables from other programs using the methods in this question. Unfortunately, as vdelecroix points out, Sage's reverse interface to Octave is too rudimentary.

sage: O = octave([1,2,3])
sage: O._sage_()
Traceback (click to the left of this block for traceback)
... 
NotImplementedError: Unable to parse output:    1 2 3

But maybe someone will write a better parser for various Octave objects... and this will work for very simple things like integers.

So one can do that at least:

sage: octave = Octave()
sage: w = octave([1, 2, 3])
sage: Matrix(ZZ, w)
[1 2 3]
sage: w = octave([pi, 5.7, 3])
sage: Matrix(RR, w)
[3.14159000000000 5.70000000000000 3.00000000000000]

Hi,

I did not find anything in the documentation. But you can at least parse the ouptut of octave as a string:

sage: v = octave('[1,5,7]')                                       
sage: str(v)
'\n\n 1 5 7\n\n'
sage: vector(map(Integer,str(v).split()))
(1, 5, 7)

The function map juste evaluate the function Integer on each element of str(v).split() which is the list ['1','5','7']. The method split of strings is very useful: it splits a string at each space character.