How to find undefined matrix in a code?
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Hello everyone, i have a matrix that presents the alarmed devices in the coverage of an access point , but i dont have alarmed devices for all access point covarege area, and you know at that time the matrix for alarm is undefined, totally empty matrix so i can't use it in the following steps. What i am asking is : is there any way to write an if statement saying if that matrix is defined do that, if it is undefined do another thing. Can you help me please?
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James Tursa
2015-3-3
If the variable is not defined at all, you can use this:
if( exist('variable_name','var') )
% variable_name is defined
else
% variable_name is not defined
end
If the variable is in fact defined but is actually empty, do this instead:
if( isempty(variable_name) )
% variable_name is empty
else
% variable_name is not empty
end
2 个评论
Cladio Andrea
2015-3-3
Guillaume
2015-3-3
In that case, for reference, the matrix is actually defined (i.e. the variable has been declared). The proper term is that it is empty (hence why you use isempty).
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