MATLAB Answers


How to convert from symbol to double?

Asked by Christian
on 19 Jan 2013


I am pretty new to MATLAB, so this might be a stupid question. However, I am encountering a problem when i try to convert a matrix of 1x1 symbols into a matrix with doubles, where the symbols are converted to doubles each. Each element in the matrix is a function of a lot of symbols, which I need somehow to convert into numbers. I have something like this:

    syms x y;
    f = function of x and y
    x = 2;
    y = 3;

However, doing this gives me f as a function of the syms x and y, and not the numbers 2 and 3... Hope you can somehow help me, as Im kinda stuck in my coding.

Regards, Christian



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2 Answers

Answer by Walter Roberson
on 19 Jan 2013
 Accepted answer


Walter Roberson
on 19 Jan 2013

Because subs() would result in symbolic numbers after substitution. double() finishes the conversion to numeric.

Azzi Abdelmalek
on 20 Jan 2013
syms x
whos y
Walter Roberson
on 20 Jan 2013

I do not have the Symbolic Toolbox to test this with.

Answer by Azzi Abdelmalek
on 19 Jan 2013
Edited by Azzi Abdelmalek
on 19 Jan 2013


suyms x

  1 Comment

Walter Roberson
on 19 Jan 2013

No, do not eval() syms!

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