sample abstract method

Matrix sample({ Iterable<int> rowIndices, Iterable<int> columnIndices, })

Samples a new Matrix from parts of this Matrix

Usage examples:

• Create a new matrix from rows of the original matrix:

import 'package:ml_linalg/matrix.dart';

void main() {
  final matrix = Matrix.fromList([
    [10, 20, 30, 40, 50],
    [22, 33, 44, 55, 66],
    [11, 89, 79, 69, 59],
  ]);
  final sampled = matrix.sample(rowIndices: [0, 2, 1, 1]);

  print(sampled);
  // [
  //   [10, 20, 30, 40, 50],
  //   [11, 89, 79, 69, 59],
  //   [22, 33, 44, 55, 66],
  //   [22, 33, 44, 55, 66],
  // ]
  //
}

• Create a new matrix from columns of the original matrix:

import 'package:ml_linalg/matrix.dart';

void main() {
  final matrix = Matrix.fromList([
    [10, 20, 30, 40, 50],
    [22, 33, 44, 55, 66],
    [11, 89, 79, 69, 59],
  ]);
  final sampled = matrix.sample(columnIndices: [4, 4, 2]);

  print(sampled);
  // [
  //   [50, 50, 30],
  //   [66, 66, 44],
  //   [59, 59, 79],
  // ]
  //
}

• Create a new matrix from both rows and columns of the original matrix:

import 'package:ml_linalg/matrix.dart';

void main() {
  final matrix = Matrix.fromList([
    [10, 20, 30, 40, 50],
    [22, 33, 44, 55, 66],
    [11, 89, 79, 69, 59],
  ]);
  final sampled = matrix.sample(
    rowIndices: [1, 1],
    columnIndices: [4, 4, 2],
  );

  print(sampled);
  // [
  //   [66, 66, 44],
  //   [66, 66, 44],
  // ]
  //
}

Implementation

Matrix sample({
  Iterable<int> rowIndices,
  Iterable<int> columnIndices,
});