How do I simplify a symbolic expression into numeric output?

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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 Comments
Ganesh P. Prajapat
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.

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Answers (3)

Walter Roberson
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.
  3 Comments

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Ned Gulley
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:
% Define your expression
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})
And the answer is...
ans =
20.3097
See the doc for subs for more information.

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

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