a small question of the sym

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xingyu
xingyu 2011-4-1
Hi I don't know how to get the numerical number after define sym. a simple code is shown as follows, how to get the value of m when x=1? Thanks
syms x n=sin(x^2); m=diff(n,x);

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Sean de Wolski
Sean de Wolski 2011-4-1
double(m)
Edit:
You'll need to use subs to fill in the value:
subs(m,'x',1)

更多回答（1 个）

xingyu
xingyu 2011-4-1
But there is something wrong. do you mean:
x=1; n=double(n); m=double(m);
but it doesn't work
  1 个评论
Walter Roberson
Walter Roberson 2011-4-1
x = 1; double(subs(n))
OR
double(subs(n,x,1)) %without assigning to x

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