# How do I simplify a symbolic expression into numeric output?

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Daniel on 20 Jan 2011
My answer for a calculation is:
ans =
(3060513257434037*x1^2)/1125899906842624 + x1 +
(3060513257434037*x2^2)/1125899906842624 + x2 +
4186413164276661/1125899906842624
How can I get MATLAB to display the answer with the fraction evaluated in decimal format?
##### 2 CommentsShowHide 1 older comment
Ganesh P. Prajapat on 10 Jun 2020
This comes out of the 'subs' command when 'syms' is associated. The simple way to have a simplified solution is, use vpa(x,d) command where x gets simplified upto d digits.

Walter Roberson on 20 Jan 2011
Use vpa() to convert fractions and numeric constants (such as Pi) into symbolic fixed-point arithmetic, such as might be used for further symbolic processing.
Use double() to convert fractions and numeric constants (such as Pi) into binary floating point arithmetic, such as might be used for further processing at the Matlab level.
Jilan Samiuddin on 2 Nov 2015
perfect!

Ned Gulley on 20 Jan 2011
It looks like you've got a symbolic expression.
You can substitute real numeric values for x1 and x2 like this:
syms x1 x2
f = (3060513257434037*x1^2)/1125899906842624 + x1 + ...
(3060513257434037*x2^2)/1125899906842624 + x2 + ...
4186413164276661/1125899906842624;
% If x1 is 1 and x2 is 2, you would type this
subs(f,{x1,x2},{1,2})
ans =
20.3097

kalpana on 12 Aug 2013
use MatlabFunction() to convert symbolic to numeric expression.

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