Question regarding matrix linear transformation

Hi @Bio_J,

To answer the first question:
Say for example you have the transformation matrix M of the general form:

\left(\begin{array}{cc} a & b\\ c & d \end{array}\right)

and vector v:

\left(\begin{array}{cc} x\\ y \end{array}\right)

If you do M * v, you would get:

\left(\begin{array}{cc} a & b\\ c & d \end{array}\right) \left(\begin{array}{cc} x\\ y \end{array}\right) = \left(\begin{array}{cc} ax + by\\ cx + dy \end{array}\right)

If you do v * M (after reshaping v so matrix multiplication is valid), you would get:

\left(\begin{array}{cc} x & y\\ \end{array}\right) \left(\begin{array}{cc} a & b\\ c & d \end{array}\right) = \left(\begin{array}{cc} ax + cy & bx + dy \end{array}\right)

So these would not be equal. In your example matrix, it seems to have given the same result since b and c were both equal to 2, but that is not always true.

For your second question, I think that is incorrect because the value of the vector v[0] and v[1] can change depending on what you set v to be. The values in the transformation matrix needs to be constant, and must not depend on the v itself.

I hope this helps!

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