time-to-botec/js/node_modules/@stdlib/strided/dispatch/lib/main.js

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/**
* @license Apache-2.0
*
* Copyright (c) 2020 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var isNonNegativeInteger = require( '@stdlib/assert/is-nonnegative-integer' ).isPrimitive;
var isPositiveInteger = require( '@stdlib/assert/is-positive-integer' );
var isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
var isFunctionArray = require( '@stdlib/assert/is-function-array' );
var isFunction = require( '@stdlib/assert/is-function' );
var isStringArray = require( '@stdlib/assert/is-string-array' ).primitives;
var isCollection = require( '@stdlib/assert/is-collection' );
var abs = require( '@stdlib/math/base/special/abs' );
var dtype = require( '@stdlib/ndarray/base/buffer-dtype' );
var indexOfTypes = require( './index_of_types.js' );
// MAIN //
/**
* Returns a strided array function interface which performs multiple dispatch.
*
* @param {(FunctionArray|Function)} fcns - list of strided array functions
* @param {StringArray} types - one-dimensional list of strided array argument data types
* @param {(Collection|null)} data - strided array function data (e.g., callbacks)
* @param {PositiveInteger} nargs - total number of strided array function interface arguments (including strides and offsets)
* @param {NonNegativeInteger} nin - number of input strided arrays
* @param {NonNegativeInteger} nout - number of output strided arrays
* @throws {TypeError} first argument must be either a function or an array of functions
* @throws {TypeError} second argument must be an array of strings
* @throws {TypeError} third argument must be an array-like object or `null`
* @throws {Error} third and first arguments must have the same number of elements
* @throws {TypeError} fourth argument must be a positive integer
* @throws {TypeError} fifth argument must be a nonnegative integer
* @throws {TypeError} sixth argument must be a nonnegative integer
* @throws {Error} fourth argument must be compatible with the specified number of input and output arrays
* @throws {Error} number of types must match the number of functions times the total number of array arguments for each function
* @throws {Error} interface must accept at least one strided input and/or output array
* @returns {Function} strided array function interface
*
* @example
* var unary = require( '@stdlib/strided/base/unary' );
* var abs = require( '@stdlib/math/base/special/abs' );
* var Float64Array = require( '@stdlib/array/float64' );
*
* var types = [
* 'float64', 'float64'
* ];
*
* var data = [
* abs
* ];
*
* var strided = dispatch( unary, types, data, 5, 1, 1 );
*
* // ...
*
* var x = new Float64Array( [ -1.0, -2.0, -3.0, -4.0, -5.0 ] );
* var y = new Float64Array( [ 0.0, 0.0, 0.0, 0.0, 0.0 ] );
*
* strided( x.length, x, 1, y, 1 );
* // y => <Float64Array>[ 1.0, 2.0, 3.0, 4.0, 5.0 ]
*/
function dispatch( fcns, types, data, nargs, nin, nout ) {
var strideArgs;
var hasOffsets;
var narrays;
var nfcns;
var iout;
var fcn;
if ( isFunction( fcns ) ) {
fcn = fcns;
} else if ( !isFunctionArray( fcns ) ) {
throw new TypeError( 'invalid argument. First argument must be either a function or an array of functions. Value: `' + fcns + '`.' );
}
if ( !isStringArray( types ) ) {
throw new TypeError( 'invalid argument. Second argument must be an array of strings. Value: `' + types + '`.' );
}
if ( !isCollection( data ) && data !== null ) {
throw new TypeError( 'invalid argument. Third argument must be an array-like object or `null`. Value: `' + data + '`.' );
}
if ( !isPositiveInteger( nargs ) ) {
throw new TypeError( 'invalid argument. Fourth argument must be a positive integer. Value: `' + nargs + '`.' );
}
if ( !isNonNegativeInteger( nin ) ) {
throw new TypeError( 'invalid argument. Fifth argument must be a nonnegative integer. Value: `' + nin + '`.' );
}
if ( !isNonNegativeInteger( nout ) ) {
throw new TypeError( 'invalid argument. Sixth argument must be a nonnegative integer. Value: `' + nout + '`.' );
}
narrays = nin + nout;
if ( narrays === 0 ) {
throw new Error( 'invalid arguments. Interface must accept at least one strided input and/or output array. Based on the provided arguments, `nin+nout` equals `0`.' );
}
if ( fcn ) {
nfcns = types.length / narrays;
if ( !isInteger( nfcns ) ) {
throw new Error( 'invalid argument. Unexpected number of types. A type must be specified for each strided input and output array for each provided strided array function.' );
}
} else {
nfcns = fcns.length;
if ( types.length !== nfcns*narrays ) {
throw new Error( 'invalid argument. Unexpected number of types. A type must be specified for each strided input and output array for each provided strided array function.' );
}
}
if ( data && data.length !== nfcns ) {
throw new Error( 'invalid argument. The third argument must have the same number of elements as the first argument.' );
}
// Determine whether the strided array interface includes offsets:
if ( (narrays*2)+1 === nargs ) {
hasOffsets = false;
} else if ( (narrays*3)+1 === nargs ) {
hasOffsets = true;
} else {
throw new Error( 'invalid argument. Fourth argument is incompatible with the number of strided input and output arrays.' );
}
// Determine the "stride" for accessing related arguments:
if ( hasOffsets ) {
strideArgs = 3;
} else {
strideArgs = 2;
}
// Compute the index of the first output strided array argument:
iout = ( nin*strideArgs ) + 1;
return dispatcher;
/**
* Strided array function interface which performs multiple dispatch.
*
* @private
* @param {integer} N - number of indexed elements
* @param {Collection} x - strided array
* @param {integer} strideX - index increment for `x`
* @param {...(Collection|integer|NonNegativeInteger)} args - array arguments (arrays, strides, and offsets)
* @throws {Error} insufficient arguments
* @throws {Error} too many arguments
* @throws {TypeError} first argument must be an integer
* @throws {TypeError} input array strides must be integers
* @throws {TypeError} output array strides must be integers
* @throws {TypeError} input array offsets must be nonnegative integers
* @throws {TypeError} output array offsets must be nonnegative integers
* @throws {TypeError} input array arguments must be array-like objects
* @throws {TypeError} output array arguments must be array-like objects
* @throws {RangeError} input array arguments must have sufficient elements based on the associated stride and the number of indexed elements
* @throws {RangeError} output array arguments must have sufficient elements based on the associated stride and the number of indexed elements
* @throws {TypeError} unable to resolve a strided array function supporting the provided array argument data types
* @returns {(Collection|Array<Collection>|void)} destination array(s)
*/
function dispatcher() {
var strides;
var offsets;
var arrays;
var dtypes;
var shape;
var argc;
var idx;
var N;
var v;
var f;
var i;
var j;
argc = arguments.length;
if ( argc !== nargs ) {
if ( argc < nargs ) {
throw new Error( 'invalid invocation. Insufficient arguments.' );
}
throw new Error( 'invalid invocation. Too many arguments.' );
}
N = arguments[ 0 ];
if ( !isInteger( N ) ) {
throw new TypeError( 'invalid argument. First argument must be an integer.' );
}
shape = [ N ];
// Strides for both input and output strided arrays are every `strideArgs` arguments beginning from the third argument...
strides = [];
for ( i = 2; i < nargs; i += strideArgs ) {
v = arguments[ i ];
if ( !isInteger( v ) ) {
if ( i < iout ) {
throw new TypeError( 'invalid argument. Input array stride argument must be an integer.' );
} else {
throw new TypeError( 'invalid argument. Output array stride argument must be an integer.' );
}
}
strides.push( v );
}
if ( hasOffsets ) {
// Offsets for both input and output strided arrays are every `strideArgs` arguments beginning from the fourth argument...
offsets = [];
for ( i = 3; i < nargs; i += strideArgs ) {
v = arguments[ i ];
if ( !isNonNegativeInteger( v ) ) {
if ( i < iout ) {
throw new TypeError( 'invalid argument. Input array offset argument must be a nonnegative integer.' );
} else {
throw new TypeError( 'invalid argument. Output array offset argument must be a nonnegative integer.' );
}
}
offsets.push( v );
}
}
// Input and output strided arrays are every `strideArgs` arguments beginning from the second argument...
arrays = [];
dtypes = [];
for ( i = 1; i < nargs; i += strideArgs ) {
v = arguments[ i ];
if ( !isCollection( v ) ) {
if ( i < iout ) {
throw new TypeError( 'invalid argument. Input array argument must be an array-like object.' );
} else {
throw new TypeError( 'invalid argument. Output array argument must be an array-like object.' );
}
}
j = (i-1) / strideArgs;
if ( hasOffsets ) {
idx = offsets[ j ] + ( (N-1)*strides[j] );
if ( N > 0 && (idx < 0 || idx >= v.length) ) {
if ( i < iout ) {
throw new RangeError( 'invalid argument. Input array argument has insufficient elements based on the associated stride and the number of indexed elements.' );
} else {
throw new RangeError( 'invalid argument. Output array argument has insufficient elements based on the associated stride and the number of indexed elements.' );
}
}
} else if ( (N-1)*abs(strides[j]) >= v.length ) {
if ( i < iout ) {
throw new RangeError( 'invalid argument. Input array argument has insufficient elements based on the associated stride and the number of indexed elements.' );
} else {
throw new RangeError( 'invalid argument. Output array argument has insufficient elements based on the associated stride and the number of indexed elements.' );
}
}
arrays.push( v );
dtypes.push( dtype( v ) || 'generic' );
}
// Resolve the strided array function satisfying the input array types:
idx = indexOfTypes( nfcns, narrays, types, narrays, 1, 0, dtypes, 1, 0 ); // eslint-disable-line max-len
// Check whether we were able to successfully resolve a strided array function:
if ( idx < 0 ) {
throw new TypeError( 'invalid arguments. Unable to resolve a strided array function supporting the provided array argument data types.' );
}
// Retrieve the strided array function:
if ( fcn ) {
f = fcn;
} else {
f = fcns[ idx ];
}
// Evaluate the strided array function:
if ( data ) {
if ( hasOffsets ) {
f( arrays, shape, strides, offsets, data[ idx ] );
} else {
f( arrays, shape, strides, data[ idx ] );
}
} else if ( hasOffsets ) {
f( arrays, shape, strides, offsets );
} else {
f( arrays, shape, strides );
}
if ( nout === 1 ) {
return arrays[ narrays-1 ];
}
if ( nout === 0 ) {
return;
}
return arrays.slice( nin );
}
}
// EXPORTS //
module.exports = dispatch;