清空筛选条件
清空筛选条件

How does symvar work?

1 次查看（过去 30 天）
sadel
sadel 2011-6-7
Hi all!
symvar 'cos(2*pi*t)'
How can I make symvar to not return 't'?
I use this: syms t
but no success.

请先登录，再回答此问题。

采纳的回答

Paulo Silva
Paulo Silva 2011-6-7
symvar gives you the symbolic variables inside one expression, you say that t is symbolic so the expression symvar('cos(2*pi*t)') gives you t, I can't imagine why you don't wan't to get the t.
  3 个评论
显示 1更早的评论
sadel
sadel 2011-6-7
If I could make symvar to identify the symbol 't' and doesn't return it then I could create
a function which evaluate only strings which represent only mathematical functions
t=0:0.1:10;
insertfunction='cos(2*pi*t))'
gh=symvar(insertfunction)
if (gh is an empty cell array)
eval(['v =0*t+ ',vectorize(gh),';'])
plot(t,v)
end
Paulo Silva
Paulo Silva 2011-6-9
t=0:0.1:10;
insertfunction='cos(2*pi*t))'
gh=symvar(insertfunction)
if (numel(gh)==1) %see if there's only one symbolic variable (just the t)
eval(['v =0*t+ ',vectorize(gh),';'])
plot(t,v)
end

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Numbers and Precision 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