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Matrix
- A matrix is rectangular array of numbers
- rows by columns → matrix
Reading a Matrix
- Elements are identified as
Matrix Laws
Adding/Subtracting Matrices
- Must have the same dimensions
Dot Product of Vectors
- The sum of the element-wise multiplication
Multiplying a Matrix and Vector
- Numbers of columns in the matrix must be the number of rows in the vector
Multiplying Two Matrices
- Rows of must equal columns of
Identity Matrix
- Identity matrix acts as in multiplication
- Anything times is itself
Transposition/Rotating
- Swap rows and columns
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