cheching exist Variable on the IF statment

6 次查看（过去 30 天）
erfan vahdat
erfan vahdat 2021-5-3
回答： DGM 2021-5-3
How to check the exist of the one variable that does not exist in if statment.
for example we have a function that need x,y variable, and we have a equation without y in it. if i run the Function it error the missing y,,,, i want to check that if it is not exist ,GIve it some value in the IF statment and then display that y is missing beside the error of the system...
  1 个评论
Adam Danz
Adam Danz 2021-5-3
编辑：Adam Danz 2021-5-3
Do you mean the variable y is not defined or the variable y is missing from the function itself?
For example, is this the problem
x = 2;
z = x+y;
or is this the problem,
x = 2;
y = 3;
fun = @(x)x^2;
z = fun(x);
Better yet, provide a working example of what you're doing.

请先登录，再进行评论。

请先登录，再回答此问题。

回答（1 个）

DGM
DGM 2021-5-3
Something like this
if ~exist('myvariable','var')
% set default value or error or whatever
end
Although using exist() during input handling is typically slower than methods using varargin

类别

在 Help Center 和 File Exchange 中查找有关 Programming 的更多信息

标签

产品


版本

R2014b

Community Treasure Hunt

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

Start Hunting!

Translated by