From Data

frombuffer

Interpret a buffer as a 1-D array.

function frombuffer(
  buffer: ArrayBuffer | TypedArray,
  dtype?: DType,
  count?: number,
  offset?: number
): NDArray

Name	Type	Default	Description
`buffer`	`ArrayBuffer \| TypedArray`	-	An object that exposes the buffer interface.
`dtype`	`DType`	`'float64'`	Data type of the returned array.
`count`	`number`	`-1`	Number of items to read. `-1` means all data in the buffer.
`offset`	`number`	`0`	Start reading the buffer from this offset (in bytes for `ArrayBuffer`, in elements for `TypedArray`).

Returns: NDArray — 1-D array created from the buffer data.

import * as np from 'numpy-ts';

const buf = new Float64Array([1.0, 2.0, 3.0, 4.0]).buffer;
const a = np.frombuffer(buf);
// array([1, 2, 3, 4])

const b = np.frombuffer(buf, 'float64', 2);
// array([1, 2])

import { frombuffer } from 'numpy-ts/core';

const buf = new Float64Array([1.0, 2.0, 3.0]).buffer;
const a = frombuffer(buf);

fromfile

Create an array from data in a file. This function requires Node.js file system access.

function fromfile(
  _file: string,
  _dtype?: DType,
  _count?: number,
  _sep?: string
): NDArray

Name	Type	Default	Description
`_file`	`string`	-	File path to read from.
`_dtype`	`DType`	`'float64'`	Data type of the returned array.
`_count`	`number`	`-1`	Number of items to read. `-1` reads the entire file.
`_sep`	`string`	`''`	Separator between items in a text file. Empty string means binary read.

Returns: NDArray — 1-D array created from file data.

fromfile requires Node.js. It will throw an error in browser environments. Use numpy-ts/node for file I/O support.

import * as np from 'numpy-ts/node';

const a = await np.loadNpy('data.npy');
// Use loadNpy for .npy files instead of fromfile

// fromfile is only available in Node.js environments
import { fromfile } from 'numpy-ts/core';
// Throws: "fromfile requires Node.js file system access"

fromfunction

Construct an array by executing a function over each coordinate. The function is called with N arguments (one per dimension) for each element, where each argument is the index along that dimension.

function fromfunction(
  func: (...args: number[]) => number,
  shape: number[],
  dtype?: DType
): NDArray

Name	Type	Default	Description
`func`	`(...args: number[]) => number`	-	Function called with coordinate indices. Should return a single number.
`shape`	`number[]`	-	Shape of the output array.
`dtype`	`DType`	`'float64'`	Data type of the output array.

Returns: NDArray — Array of the given shape, with each element set to func(i, j, ...).

import * as np from 'numpy-ts';

// Sum of indices
const a = np.fromfunction((i, j) => i + j, [3, 3]);
// array([[0, 1, 2],
//        [1, 2, 3],
//        [2, 3, 4]])

// Boolean-like: 1 where i == j
const b = np.fromfunction((i, j) => i === j ? 1 : 0, [3, 3]);
// array([[1, 0, 0],
//        [0, 1, 0],
//        [0, 0, 1]])

import { fromfunction } from 'numpy-ts/core';

const a = fromfunction((i, j) => i * 10 + j, [3, 4]);

fromiter

Create a 1-D array from an iterable.

function fromiter(
  iter: Iterable<number>,
  dtype?: DType,
  count?: number
): NDArray

Name	Type	Default	Description
`iter`	`Iterable<number>`	-	Any iterable yielding numbers (arrays, generators, sets, etc.).
`dtype`	`DType`	`'float64'`	Data type of the output array.
`count`	`number`	`-1`	Maximum number of items to read. `-1` reads all items.

Returns: NDArray — 1-D array from the iterable values.

import * as np from 'numpy-ts';

function* fibonacci() {
  let a = 0, b = 1;
  while (true) { yield a; [a, b] = [b, a + b]; }
}

const a = np.fromiter(fibonacci(), 'float64', 8);
// array([0, 1, 1, 2, 3, 5, 8, 13])

const b = np.fromiter(new Set([10, 20, 30]));
// array([10, 20, 30])

import { fromiter } from 'numpy-ts/core';

const a = fromiter([1, 2, 3, 4, 5]);

fromstring

Create a 1-D array from a string of numbers.

function fromstring(
  string: string,
  dtype?: DType,
  count?: number,
  sep?: string
): NDArray

Name	Type	Default	Description
`string`	`string`	-	A string containing the data.
`dtype`	`DType`	`'float64'`	Data type of the output array.
`count`	`number`	`-1`	Number of items to read. `-1` reads all items.
`sep`	`string`	whitespace	Separator between values. Defaults to whitespace splitting.

Returns: NDArray — 1-D array parsed from the string.

import * as np from 'numpy-ts';

const a = np.fromstring('1 2 3 4 5');
// array([1, 2, 3, 4, 5])

const b = np.fromstring('1.5,2.5,3.5', 'float64', -1, ',');
// array([1.5, 2.5, 3.5])

const c = np.fromstring('10 20 30 40 50', 'int32', 3);
// array([10, 20, 30])

import { fromstring } from 'numpy-ts/core';

const a = fromstring('1 2 3 4 5');
const b = fromstring('1.5,2.5,3.5', 'float64', -1, ',');

meshgrid

Return coordinate matrices from coordinate vectors. Given N 1-D arrays, meshgrid returns N N-D arrays for vectorized evaluations of N-D scalar fields.

function meshgrid(...args: (ArrayLike | { indexing?: 'xy' | 'ij'; })[]): NDArray[]

Name	Type	Default	Description
`...args`	`(ArrayLike \| { indexing?: 'xy' \| 'ij' })[]`	-	1-D arrays representing coordinates of a grid, optionally followed by options.

Returns: NDArray[] — Array of N-D coordinate arrays, one per input.

import * as np from 'numpy-ts';

const x = np.array([1, 2, 3]);
const y = np.array([4, 5]);

const [X, Y] = np.meshgrid(x, y);
// X = array([[1, 2, 3],
//            [1, 2, 3]])
// Y = array([[4, 4, 4],
//            [5, 5, 5]])

// Evaluate x^2 + y^2 on the grid
const Z = np.add(np.square(X), np.square(Y));

import { meshgrid, array, add, square } from 'numpy-ts/core';

const x = array([1, 2, 3]);
const y = array([4, 5]);
const [X, Y] = meshgrid(x, y);
const Z = add(square(X), square(Y));

Overview

NDArray

Array Creation

Math

Array Manipulation

Reductions & Statistics

Linear Algebra

Logic & Comparison

Sorting & Searching

Set Operations

Bitwise

Indexing

Gradient & Differences

Polynomials

Random (np.random)

FFT (np.fft)

I/O

Utilities

frombuffer

fromfile

fromfunction

fromiter

fromstring

meshgrid

​frombuffer

​fromfile

​fromfunction

​fromiter

​fromstring

​meshgrid

frombuffer

fromfile

fromfunction

fromiter

fromstring

meshgrid