ndarray

Multidimensional arrays.

Installation

npm install @stdlib/ndarray

Usage

var ns = require( '@stdlib/ndarray' );

ns

ndarray namespace.

var o = ns;
// returns {...}

Creation

The namespace exports the following functions to create multidimensional arrays:

• array( [buffer,] [options] ): create a multidimensional array.
• copy( x[, options] ): copy an input ndarray to a new ndarray having the same shape and data type.
• ndarray( dtype, buffer, shape, strides, offset, order[, options] ): multidimensional array constructor.
• emptyLike( x[, options] ): create an uninitialized ndarray having the same shape and data type as a provided ndarray.
• empty( shape[, options] ): create an uninitialized ndarray having a specified shape and data type.
• falsesLike( x[, options] ): create an ndarray filled with false values and having the same shape and data type as a provided ndarray.
• falses( shape[, options] ): create an ndarray filled with false values and having a specified shape and data type.
• FancyArray( dtype, buffer, shape, strides, offset, order[, options] ): fancy multidimensional array constructor.
• scalar2ndarrayLike( x, value[, options] ): convert a scalar value to a zero-dimensional ndarray having the same data-type as a provided ndarray.
• scalar2ndarray( value[, options] ): convert a scalar value to a zero-dimensional ndarray.
• nansLike( x[, options] ): create a NaN-filled ndarray having the same shape and data type as a provided ndarray.
• nans( shape[, options] ): create a NaN-filled ndarray having a specified shape and data type.
• ndarraylike2ndarray( x[, options] ): convert an ndarray-like object to an ndarray.
• onesLike( x[, options] ): create a ones-filled ndarray having the same shape and data type as a provided ndarray.
• ones( shape[, options] ): create a ones-filled ndarray having a specified shape and data type.
• ndarray2fancy( x[, options] ): convert an ndarray to an object supporting fancy indexing.
• truesLike( x[, options] ): create an ndarray filled with true values and having the same shape and data type as a provided ndarray.
• trues( shape[, options] ): create an ndarray filled with true values and having a specified shape and data type.
• zerosLike( x[, options] ): create a zero-filled ndarray having the same shape and data type as a provided ndarray.
• zeros( shape[, options] ): create a zero-filled ndarray having a specified shape and data type.

Manipulation

The namespace exports the following functions to manipulate multidimensional arrays:

• broadcastArray( x, shape ): broadcast an ndarray to a specified shape.
• broadcastArrays( ...arrays ): broadcast ndarrays to a common shape.
• broadcastScalarLike( x, value[, options] ): broadcast a scalar value to an ndarray having the same shape and data-type as a provided input ndarray.
• broadcastScalar( value, shape[, options] ): broadcast a scalar value to an ndarray of a specified shape.
• colcat( arrays ): concatenate a list of one-dimensional or two-dimensional ndarrays as columns.
• concat( arrays[, options] ): concatenate a list of ndarrays along a specified ndarray dimension.
• concat1d( ...arrays ): return a one-dimensional ndarray formed by concatenating provided input arguments.
• diagonal( x[, options] ): return a read-only view of the diagonal of a matrix (or stack of matrices).
• fillBy( x, fcn[, thisArg] ): fill an input ndarray according to a callback function.
• fillSlice( x, value, ...s[, options] ): fill an input ndarray view with a specified value.
• fill( x, value ): fill an input ndarray with a specified value.
• flattenBy( x[, options], fcn[, thisArg] ): flatten an ndarray according to a callback function.
• flattenFromBy( x, dim[, options], fcn[, thisArg] ): flatten an ndarray according to a callback function starting from a specified dimension.
• flattenFrom( x, dim[, options] ): return a copy of an input ndarray where all dimensions of the input ndarray are flattened starting from a specified dimension.
• flatten( x[, options] ): return a flattened copy of an input ndarray.
• fliplr( x ): return a read-only view of an input ndarray in which the order of elements along the last dimension is reversed.
• flipud( x ): return a read-only view of an input ndarray in which the order of elements along the second-to-last dimension is reversed.
• hconcat( arrays ): concatenate a list of ndarrays along the last dimension.
• map( x[, options], fcn[, thisArg] ): apply a callback function to elements in an input ndarray and assign results to elements in a new output ndarray.
• maybeBroadcastArray( x, shape ): broadcast an ndarray to a specified shape if and only if the specified shape differs from the provided ndarray's shape.
• maybeBroadcastArrays( arrays ): broadcast ndarrays to a common shape.
• pop( x[, options] ): return an array containing a read-only truncated view of an input ndarray and a read-only view of the last element(s) along a specified dimension.
• prependSingletonDimensions( x, n ): return a read-only view of an input ndarray with a specified number of prepended singleton dimensions.
• push( x, ...values ): return a one-dimensional ndarray formed by appending provided scalar values to a one-dimensional input ndarray.
• removeSingletonDimensions( x ): return a read-only view of an input ndarray with singleton dimensions removed.
• reverseDimension( x, dim ): return a read-only view of an input ndarray in which the order of elements along a specified dimension is reversed.
• reverseDimensions( x, dims ): return a read-only view of an input ndarray in which the order of elements along specified dimensions is reversed.
• reverse( x ): return a read-only view of an input ndarray in which the order of elements along each dimension is reversed.
• rot180( x[, options] ): return a read-only view of an input ndarray rotated 180 degrees in a specified plane.
• rot90( x[, options] ): return a read-only view of an input ndarray rotated 90 degrees in a specified plane.
• rotl90( x, k ): return a read-only view of a matrix (or a stack of matrices) rotated 90 degrees counterclockwise.
• rotr90( x, k ): return a read-only view of a matrix (or a stack of matrices) rotated 90 degrees clockwise.
• rowcat( arrays ): concatenate a list of one-dimensional or two-dimensional ndarrays as rows.
• shift( x[, options] ): return an array containing a read-only truncated view of an input ndarray and a read-only view of the first element(s) along a specified dimension.
• sliceAssign( x, y, ...s[, options] ): assign element values from a broadcasted input ndarray to corresponding elements in an output ndarray view.
• sliceDimensionFrom( x, dim, start[, options] ): return a read-only shifted view of an input ndarray along a specified dimension.
• sliceDimensionTo( x, dim, stop[, options] ): return a read-only truncated view of an input ndarray along a specified dimension.
• sliceDimension( x, dim, slice[, options] ): return a read-only view of an input ndarray when sliced along a specified dimension.
• sliceFrom( x, ...start[, options] ): return a read-only shifted view of an input ndarray.
• sliceTo( x, ...stop[, options] ): return a read-only truncated view of an input ndarray.
• slice( x, ...s[, options] ): return a read-only view of an input ndarray.
• spreadDimensions( ndims, x, dims ): return a read-only view of an input ndarray where the dimensions of the input ndarray are expanded to a specified dimensionality by spreading dimensions to specified dimension indices and inserting dimensions of size one for the remaining dimensions.
• toFlippedlr( x ): return a new ndarray where the order of elements along the last dimension of an input ndarray is reversed.
• toFlippedud( x ): return a new ndarray where the order of elements along the second-to-last dimension of an input ndarray is reversed.
• toReversedDimension( x[, options] ): return a new ndarray where the order of elements of an input ndarray along a specified dimension is reversed.
• toReversedDimensions( x, dims ): return a new ndarray where the order of elements of an input ndarray along specified dimensions is reversed.
• toReversed( x ): return a new ndarray where the order of elements of an input ndarray is reversed along each dimension.
• toRot180( x[, options] ): return a new ndarray where an input ndarray is rotated 180 degrees in a specified plane.
• toRot90( x[, options] ): return a new ndarray where an input ndarray is rotated 90 degrees in a specified plane.
• toRotl90( x, k ): return a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees counterclockwise.
• toRotr90( x, k ): return a new ndarray where a matrix (or a stack of matrices) is rotated 90 degrees clockwise.
• toTransposed( x ): return a new ndarray containing the elements of an input ndarray but whose last two dimensions are transposed.
• toUnflattened( x, dim, sizes ): return a new ndarray in which a specified dimension of an input ndarray is expanded over multiple dimensions.
• transpose( x ): return a read-only view of an input ndarray in which the last two dimensions are transposed.
• unflatten( x, dim, sizes ): return a read-only view of an input ndarray in which a specified dimension is expanded over multiple dimensions.
• unshift( x, ...values ): return a one-dimensional ndarray formed by prepending provided scalar values to a one-dimensional input ndarray.
• vconcat( arrays ): concatenate a list of ndarrays along the second-to-last dimension.
• ndarrayWith( x, indices, value ): return a new ndarray with the element at a specified index replaced by a provided value.

Search

The namespace exports the following functions to search multidimensional arrays:

• anyBy( x[, options], predicate[, thisArg] ): test whether at least one element along one or more ndarray dimensions passes a test implemented by a predicate function.
• any( x[, options] ): test whether at least one element along one or more ndarray dimensions is truthy.
• countFalsy( x[, options] ): count the number of falsy elements along one or more ndarray dimensions.
• countIf( x[, options], predicate[, thisArg] ): count the number of truthy elements along one or more ndarray dimensions.
• countTruthy( x[, options] ): count the number of truthy elements along one or more ndarray dimensions.
• everyBy( x[, options], predicate[, thisArg] ): test whether all elements along one or more ndarray dimensions pass a test implemented by a predicate function.
• every( x[, options] ): test whether every element along one or more ndarray dimensions is truthy.
• filterMap( x[, options], fcn[, thisArg] ): filter and map elements in an input ndarray to elements in a new output ndarray according to a callback function.
• filter( x[, options], predicate[, thisArg] ): return a shallow copy of an ndarray containing only those elements which pass a test implemented by a predicate function.
• findLast( x[, options], predicate[, thisArg] ): return a new ndarray containing the last elements which pass a test implemented by a predicate function along one or more ndarray dimensions.
• find( x[, options], predicate[, thisArg] ): return a new ndarray containing the first elements which pass a test implemented by a predicate function along one or more ndarray dimensions.
• includes( x, searchElement[, options] ): test whether an ndarray contains a specified value along one or more dimensions.
• reject( x[, options], predicate[, thisArg] ): return a shallow copy of an ndarray containing only those elements which fail a test implemented by a predicate function.
• someBy( x, n[, options], predicate[, thisArg] ): test whether at least n elements along one or more ndarray dimensions pass a test implemented by a predicate function.
• some( x, n[, options] ): test whether at least n elements along one or more ndarray dimensions are truthy.

Inspection

The namespace exports the following functions to inspect multidimensional arrays:

• dataBuffer( x ): return the underlying data buffer of a provided ndarray.
• dtype( x ): return the data type of a provided ndarray.
• flag( x, name ): return a specified flag for a provided ndarray.
• flags( x ): return the flags of a provided ndarray.
• ndims( x ): return the number of ndarray dimensions.
• numelDimension( x, dim ): return the size (i.e., number of elements) of a specified dimension for a provided ndarray.
• numel( x ): return the number of elements in an ndarray.
• offset( x ): return the index offset specifying the underlying buffer index of the first iterated ndarray element.
• order( x ): return the layout order of a provided ndarray.
• shape( x ): return the shape of a provided ndarray.
• stride( x, dim ): return the stride along a specified dimension for a provided ndarray.
• strides( x ): return the strides of a provided ndarray.

Indexing

The namespace exports the following functions to index multidimensional arrays:

• at( x[, ...indices] ): return an ndarray element.
• first( x[, options] ): return a read-only view of the first element (or subarray) along one or more ndarray dimensions.
• ind2sub( shape, idx[, options] ): convert a linear index to an array of subscripts.
• indexModes(): list of ndarray index modes.
• ndindex( x[, options] ): ndarray index constructor.
• last( x[, options] ): return a read-only view of the last element (or subarray) along one or more ndarray dimensions.
• sub2ind( shape, ...subscripts[, options] ): convert subscripts to a linear index.

Conversion

The namespace exports the following functions to convert multidimensional arrays:

• ndarraylike2scalar( x ): convert an ndarray-like object to a scalar value.
• ndarray2array( x ): convert an ndarray to a generic array.
• ndarray2json( x ): serialize an ndarray as a JSON object.
• ndarray2localeString( x[, locales[, options]] ): serialize an ndarray as a locale-aware string.
• ndarray2string( x ): serialize an ndarray as a string.

Data Types

The namespace exports the following functions for working with multidimensional array data types:

• castingModes(): list of ndarray casting modes.
• DataType( value[, options] ): data type constructor.
• dtypes( [kind] ): list of ndarray data types.
• inputCastingPolicies(): list of input ndarray casting policies.
• minDataType( value ): determine the minimum ndarray data type of the closest "kind" necessary for storing a provided scalar value.
• mostlySafeCasts( [dtype] ): return a list of ndarray data types to which a provided ndarray data type can be safely cast and, for floating-point data types, can be downcast.
• nextDataType( [dtype] ): return the next larger ndarray data type of the same kind.
• outputDataTypePolicies(): list of output ndarray data type policies.
• promotionRules( [dtype1, dtype2] ): return the ndarray data type with the smallest size and closest "kind" to which ndarray data types can be safely cast.
• safeCasts( [dtype] ): return a list of ndarray data types to which a provided ndarray data type can be safely cast.
• sameKindCasts( [dtype] ): return a list of ndarray data types to which a provided ndarray data type can be safely cast or cast within the same "kind".

Sub-namespaces

The namespace contains the following sub-namespaces:

• base: base ndarray.
• iter: multidimensional array iterators.
• vector: vector constructors and associated utilities.

Utilities

The namespace contains the following multidimensional array utility functions:

• defaults(): default ndarray settings.
• dispatch( fcns, types, data, nargs, nin, nout ): create an ndarray function interface which performs multiple dispatch.
• forEach( x, fcn[, thisArg] ): invoke a callback function once for each ndarray element.
• orders(): list of ndarray orders.

Examples

var objectKeys = require( '@stdlib/utils/keys' );
var ns = require( '@stdlib/ndarray' );

console.log( objectKeys( ns ) );

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2026. The Stdlib Authors.