mirror of
https://github.com/Llewellynvdm/php-ml.git
synced 2024-11-25 22:37:34 +00:00
130 lines
1.8 KiB
Markdown
130 lines
1.8 KiB
Markdown
# Matrix
|
|
|
|
Class that wraps PHP arrays to mathematical matrix.
|
|
|
|
### Creation
|
|
|
|
To create Matrix use simple arrays:
|
|
|
|
```
|
|
$matrix = new Matrix([
|
|
[3, 3, 3],
|
|
[4, 2, 1],
|
|
[5, 6, 7],
|
|
]);
|
|
```
|
|
|
|
You can also create Matrix (one dimension) from flat array:
|
|
|
|
```
|
|
$flatArray = [1, 2, 3, 4];
|
|
$matrix = Matrix::fromFlatArray($flatArray);
|
|
```
|
|
|
|
### Matrix data
|
|
|
|
Methods for reading data from Matrix:
|
|
|
|
```
|
|
$matrix->toArray(); // cast matrix to PHP array
|
|
$matrix->getRows(); // rows count
|
|
$matrix->getColumns(); // columns count
|
|
$matrix->getColumnValues($column=4); // get values from given column
|
|
```
|
|
|
|
### Determinant
|
|
|
|
Read more about [matrix determinant](https://en.wikipedia.org/wiki/Determinant).
|
|
|
|
```
|
|
$matrix = new Matrix([
|
|
[3, 3, 3],
|
|
[4, 2, 1],
|
|
[5, 6, 7],
|
|
]);
|
|
|
|
$matrix->getDeterminant();
|
|
// return -3
|
|
```
|
|
|
|
### Transpose
|
|
|
|
Read more about [matrix transpose](https://en.wikipedia.org/wiki/Transpose).
|
|
|
|
```
|
|
$matrix->transpose();
|
|
// return new Matrix
|
|
```
|
|
|
|
### Multiply
|
|
|
|
Multiply Matrix by another Matrix.
|
|
|
|
```
|
|
$matrix1 = new Matrix([
|
|
[1, 2, 3],
|
|
[4, 5, 6],
|
|
]);
|
|
|
|
$matrix2 = new Matrix([
|
|
[7, 8],
|
|
[9, 10],
|
|
[11, 12],
|
|
]);
|
|
|
|
$matrix1->multiply($matrix2);
|
|
|
|
// result $product = [
|
|
// [58, 64],
|
|
// [139, 154],
|
|
//];
|
|
```
|
|
|
|
### Divide by scalar
|
|
|
|
You can divide Matrix by scalar value.
|
|
|
|
```
|
|
$matrix->divideByScalar(2);
|
|
```
|
|
|
|
### Inverse
|
|
|
|
Read more about [invertible matrix](https://en.wikipedia.org/wiki/Invertible_matrix)
|
|
|
|
```
|
|
$matrix = new Matrix([
|
|
[3, 4, 2],
|
|
[4, 5, 5],
|
|
[1, 1, 1],
|
|
]);
|
|
|
|
$matrix->inverse();
|
|
|
|
// result $inverseMatrix = [
|
|
// [0, -1, 5],
|
|
// [1 / 2, 1 / 2, -7 / 2],
|
|
// [-1 / 2, 1 / 2, -1 / 2],
|
|
//];
|
|
|
|
```
|
|
|
|
### Cross out
|
|
|
|
Cross out given row and column from Matrix.
|
|
|
|
```
|
|
$matrix = new Matrix([
|
|
[3, 4, 2],
|
|
[4, 5, 5],
|
|
[1, 1, 1],
|
|
]);
|
|
|
|
$matrix->crossOut(1, 1)
|
|
|
|
// result $crossOuted = [
|
|
// [3, 2],
|
|
// [1, 1],
|
|
//];
|
|
```
|