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How to obtain values symbolically

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Vicky
Vicky 2013-2-22
关闭: MATLAB Answer Bot 2021-8-20
Hi! Im using Matlab version 7.9.0(R2009b) and i would like to sum e.g. first 10 terms of expression c_i*x^i, where c_i should be obtained symbolically. how should i do that, so that this expression is dependent on x / function of x (so when i enter exact number for x, i get real number - not expression with c_i).

回答(2 个)

Azzi Abdelmalek
Azzi Abdelmalek 2013-2-22
编辑:Azzi Abdelmalek 2013-2-22
EDIT
c=sym('c',[1 10])
x=sym('x')
f=@(x,n)sum(c(1:n).*x.^(1:n))
f(x,5)
  8 个评论
Walter Roberson
Walter Roberson 2013-2-23
If that is the complete instruction you are given, then the c_i are just the symbolic variables, and you will not be able to complete the second part.
If there are instructions before that point, then you might be able to proceed further.
Vicky
Vicky 2013-2-23
there should be sth else, but i cant find the answer...thank You, Walter, anyway.

bym
bym 2013-2-23
alternative:
c =sym(1:10)
f = @(x) sum(c.*x.^(1:length(c)));

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