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130 lines
1.8 KiB
Markdown
130 lines
1.8 KiB
Markdown
# Matrix
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Class that wraps PHP arrays to mathematical matrix.
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### Creation
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To create Matrix use simple arrays:
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```
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$matrix = new Matrix([
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[3, 3, 3],
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[4, 2, 1],
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[5, 6, 7],
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]);
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```
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You can also create Matrix (one dimension) from flat array:
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```
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$flatArray = [1, 2, 3, 4];
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$matrix = Matrix::fromFlatArray($flatArray);
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```
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### Matrix data
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Methods for reading data from Matrix:
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```
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$matrix->toArray(); // cast matrix to PHP array
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$matrix->getRows(); // rows count
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$matrix->getColumns(); // columns count
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$matrix->getColumnValues($column=4); // get values from given column
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```
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### Determinant
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Read more about [matrix determinant](https://en.wikipedia.org/wiki/Determinant).
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```
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$matrix = new Matrix([
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[3, 3, 3],
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[4, 2, 1],
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[5, 6, 7],
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]);
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$matrix->getDeterminant();
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// return -3
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```
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### Transpose
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Read more about [matrix transpose](https://en.wikipedia.org/wiki/Transpose).
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```
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$matrix->transpose();
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// return new Matrix
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```
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### Multiply
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Multiply Matrix by another Matrix.
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```
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$matrix1 = new Matrix([
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[1, 2, 3],
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[4, 5, 6],
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]);
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$matrix2 = new Matrix([
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[7, 8],
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[9, 10],
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[11, 12],
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]);
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$matrix1->multiply($matrix2);
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// result $product = [
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// [58, 64],
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// [139, 154],
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//];
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```
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### Divide by scalar
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You can divide Matrix by scalar value.
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```
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$matrix->divideByScalar(2);
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```
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### Inverse
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Read more about [invertible matrix](https://en.wikipedia.org/wiki/Invertible_matrix)
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```
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$matrix = new Matrix([
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[3, 4, 2],
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[4, 5, 5],
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[1, 1, 1],
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]);
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$matrix->inverse();
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// result $inverseMatrix = [
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// [0, -1, 5],
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// [1 / 2, 1 / 2, -7 / 2],
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// [-1 / 2, 1 / 2, -1 / 2],
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//];
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```
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### Cross out
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Cross out given row and column from Matrix.
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```
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$matrix = new Matrix([
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[3, 4, 2],
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[4, 5, 5],
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[1, 1, 1],
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]);
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$matrix->crossOut(1, 1)
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// result $crossOuted = [
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// [3, 2],
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// [1, 1],
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//];
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```
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