Store only numbers from user input

Hi guys

Is there a way to store only the numbers from lets say an input of the type S^2+67*s+98

Answer 1

[Walter Roberson]

numstrs = regexp(TheString, '-?\d+', 'match');

then convert each of the cell strings returned in numstrs to numeric form. The -? part is to recognize an optional negative sign.

If you want to be able to accept floating point numbers, or if you want to recognize fractions as being numbers, or if you want to recognize pi as being a number, then the task gets more difficult.

[Raldi]

No i think this will do, thank you Walter.

Answer 2

[Jan]

Another approach from the times of Matlab 5.3 without REGEXP:

S = 'S^2+67*s+98';
S((S < '0' | S > '9') & S ~= '.') = ' ';
N = sscanf(S, '%g');

[Raldi]

i think i get it now...thanks guys

[Raldi]

Seems that i have another problem now. What if i only need the numbers that are lets say just before the letter S. I tried to figure it out from the matlab's help but with no luck.

[Walter Roberson]

Answered in your newer question.