Re: Octave: assume() command in symbolic toolbox.

[Colin Macdonald]

On 25/01/17 08:53, Constantine Frangos wrote:
> (1) How is the assume() command applied in order to limit
> a symbolic variable w to a real interval (a, b], for example,
> (-pi/2, pi/2], [0, pi], (-pi, pi], etc?

Unfortunately, I don't know any way to do this at the moment.  If you're 
using "solve", perhaps you can pass inequality constraints to it?

The symbolic package uses Sympy; here is a perhaps helpful thread about 
this in Sympy:

http://stackoverflow.com/questions/19553652/sympy-limit-symbol-variable-to-interval

> (2) The documentation for the assume() command states that it
> can be used as follows:
>
> sym X = assume (X, COND1, COND2, …)
>
> Some of the possible values for cond1, cond2, etc seem to be
> 'positive', 'negative', 'integer', 'real'.
>
> What are all the other possible values?

See "help assumptions" and in particular:

>> assumptions ('possible')

The upcoming 2.5.0 release will have many more options (but still no 
general algebraic constraints).

best,
Colin