Re: strings

[Christoph Mecklenbraeuker]

Hi Allan,

You asked:
> In octave, I can't seem to define 2-D string arrays.
> I also cannot do simple subscripting. For example:
> str=["abc";"def"]
> s1=str(1:2)
> Can anyone help.


There exists an internal Octave variable called

        implicit_str_to_num_ok

which can be set to "true"

        octave:1> implicit_str_to_num_ok = "true";

After you have set this, you can define

        octave:2>str = ["abc";"def"]
        str =
 
           97   98   99
          100  101  102

where the matrix str is automatically converted to numeric type. Now

        octave:3> s1=str(1:2)
        s1 =

           97 100

works if you have set the variable

        do_fortran_indexing = "true"

If you want to set the type of a variable from 'numeric' to 'string',
you can use the function setstr()

        octave:4> s2 = setstr(str)
        s2 = adbecf

But this is maybe not what you want?

> Also do the equivalent of MEX files exist for octave?

Yes they do, but do not work on every system. They are called
'dynamically linked functions' and you need the GNU dynamic linker 'dld'.
In my octave 1.1.0 manual you can find the relevant info in section 5.8

All the best,
Christoph




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Christoph Mecklenbraeuker             | 
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Ruhr Universitaet Bochum              | Fax: +49(234) 709 4261
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