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matlabstructure

Matlab Structures: How to compare the contents of structure? Getting the following error

I have the structure below with the value. When I try to compare the value of the field I get the error below. What can I do?

Input

XYZ.Element_2 =='Fundamental'
if XYZ.Element_2 == 'RMS'
    var33=1
else
    var33=0
end

Output

Matrix dimensions must agree.

Error in sample50main (line 38)
if XYZ.Element_2 == 'RMS'
Solution

  • Looks like the issue is that MATLAB is trying to do a character array comparison and since those arrays do not have an equal number of characters a dimension error is thrown. An implementation that could resolve this may be by doing a string comparison using double quotes "". Alternatively, you can use the strcmp() function as described in the comment above. Below are both implementations:

    Method 1: Using Double Quotes

    Condition True:

    XYZ.Element_2 = 'Fundamental';

if XYZ.Element_2 == "RMS"
    var33 = 1;
else
    var33 = 0;
end

    Condition False:

    XYZ.Element_2 = 'RMS';

if XYZ.Element_2 == "RMS"
    var33 = 1;
else
    var33 = 0;
end

    Method 2: Using strcmp() Function

    Condition True:

    XYZ.Element_2 = 'Fundamental';

if strcmp(XYZ.Element_2,'RMS')
    var33 = 1;
else
    var33 = 0;
end

    Condition Flase:

    XYZ.Element_2 = 'RMS';

if strcmp(XYZ.Element_2,'RMS')
    var33 = 1;
else
    var33 = 0;
end

    Ran using MATLAB R2019b