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Returning an object from a method

Hullo,
I have built a library of Matrix functions and now I want to test those functions. I have built a simple program to do this, and connected the library to this application. In my program I do the following;-
1 Use a Constructor to create the matrix of the correct size and with a value assigned to each location in the array.
2 Use a library method (matMultTD()), to multiply two matrices together and return a Matrix object.
fitLeft = new Matrix(2, 2, 1);
fitLeft.matMultTD(obsLeft, obsLeft);
I have followed the actions in the debugger and the matMultTD method does what is it supposed to do, but obviously the way that I have linked the Matrix output from the matMultTD method does not work because the fitLeft Matrix retains the original values. What am I doing wrong?
Comments
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fitLeft object values won't be modified, just because one of its methods is called. What is the matMultTD method? And why is it called with obsLeft passed as parameter twice?
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Hej dvohra21, Thank you for your response, I appreciate it. I have found that by modifying the method matMultTD and replacing the second line of code above with;-
fitLeft = obsLeft.matMultTD(obsLeft);
I get the right answer.
I have obsLeft twice (or the owning and the passed objects in the revised version) because the method is a general method to multiply the transpose of one 2-D array by a second 2-D array, ie the arrays need to have identical values in their rows but not in their columns.
But I have a question or comment. I deliberately created the fitLeft matrix to be too large in the constructor above, yet it returned the correct answer. Why is this?
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As no class definitions that include constructor/s and methods/s have been posted it may be a guessing puzzle as to what is being computed with matrices. Please post class definitions including constructor/s and methods/s.