How to evaluate a matlab symbolic expression properly?

Question

Lets say I have a matrix like this:

syms p;
K = [p^2+3 0; 2 5*p];
p_initial = 2;

Whats the proper/fastest way of getting K(p_initial), that is the resulting matrix if I insert 2 for p. Further, I want the resulting matrix to be of type double, not of symbolic type.

Thanks in advance

Consider using Google **before** stackoverflow. – Ander Biguri Mar 19 '18 at 13:40 — Ander Biguri, Mar 19 '18 at 13:40

score 0 · Accepted Answer · answered Mar 19 '18 at 13:39

0

Use subs to substitute variables in symbolic expressions

subs(K,'p',p_initial)

ans =

[ 7,  0]
[ 2, 10]

answered Mar 19 '18 at 13:39

Ander Biguri

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And then just using double() on the result? – Doc Mar 19 '18 at 13:42
Thanks, I actually did though: "Further, I want the resulting matrix to be of type double, not of symbolic type.". – Doc Mar 19 '18 at 13:44

How to evaluate a matlab symbolic expression properly?

1 Answers1