time-to-botec

Benchmark sampling in different programming languages
Log | Files | Refs | README

main.js (2016B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var incrmean = require( './../../../incr/mean' );
     24 var signum = require( '@stdlib/math/base/special/signum' );
     25 var kroneckerDelta = require( '@stdlib/math/base/special/kronecker-delta' );
     26 
     27 
     28 // MAIN //
     29 
     30 /**
     31 * Returns an accumulator function which incrementally computes the mean directional accuracy.
     32 *
     33 * @returns {Function} accumulator function
     34 *
     35 * @example
     36 * var accumulator = incrmda();
     37 *
     38 * var m = accumulator();
     39 * // returns null
     40 *
     41 * m = accumulator( 2.0, 3.0 );
     42 * // returns 1.0
     43 *
     44 * m = accumulator( -5.0, 4.0 );
     45 * // returns 0.5
     46 *
     47 * m = accumulator();
     48 * // returns 0.5
     49 */
     50 function incrmda() {
     51 	var mean;
     52 	var FLG;
     53 	var f0;
     54 	var a0;
     55 
     56 	mean = incrmean();
     57 	return accumulator;
     58 
     59 	/**
     60 	* If provided a value, the accumulator function returns an updated mean directional accuracy. If not provided a value, the accumulator function returns the current mean directional accuracy.
     61 	*
     62 	* @private
     63 	* @param {number} [f] - forecast value
     64 	* @param {number} [a] - actual value
     65 	* @returns {(number|null)} mean directional accuracy or null
     66 	*/
     67 	function accumulator( f, a ) {
     68 		var sf;
     69 		var sa;
     70 		if ( arguments.length === 0 ) {
     71 			return mean();
     72 		}
     73 		if ( FLG === void 0 ) {
     74 			FLG = true;
     75 			f0 = f;
     76 			a0 = a;
     77 		}
     78 		sf = signum( f-f0 );
     79 		sa = signum( a-a0 );
     80 		f0 = f;
     81 		a0 = a;
     82 		return mean( kroneckerDelta( sf, sa ) );
     83 	}
     84 }
     85 
     86 
     87 // EXPORTS //
     88 
     89 module.exports = incrmda;