Evaluating a function defined by "sym" command

1 次查看（过去 30 天）
SAZZAD HOSSAIN
SAZZAD HOSSAIN 2013-11-19
评论： SAZZAD HOSSAIN 2013-11-19
Hello
I am using "sym" command to define the variables in small expressions that form the elements of a matrix. Eventually i have to diagonalize the matrix to find eigenvalues. With sym command lets say i define -
f = a*x^2+b*x;
Now i want to evaluate the magnitude of 'f' by putting in numerical values for a,b and x. a and b are constants but x would be an array. How can define the values of a,b and x to find numerical answer for f under these circumstance?
Thanks

请先登录，再回答此问题。

采纳的回答

Sean de Wolski
Sean de Wolski 2013-11-19
Use subs:
syms a b x
f = a*x^2+b*x;
subs(f,{a,b,x},{1,2,magic(3)})
And for more info:
doc subs

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Symbolic Math Toolbox 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by