validate.js (1377B)
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 isPositive = require( '@stdlib/assert/is-positive-number' ).isPrimitive; 24 25 26 // MAIN // 27 28 /** 29 * Validates parameters. 30 * 31 * @private 32 * @param {PositiveNumber} alpha - shape parameter 33 * @param {PositiveNumber} beta - scale parameter 34 * @returns {(Error|null)} error or null 35 * 36 * @example 37 * var err = validate( 1.0, 2.0 ); 38 * if ( err ) { 39 * throw err; 40 * } 41 */ 42 function validate( alpha, beta ) { 43 if ( !isPositive( alpha ) ) { 44 return new TypeError( 'invalid argument. `alpha` must be a positive number. Value: `' + alpha + '`.' ); 45 } 46 if ( !isPositive( beta ) ) { 47 return new TypeError( 'invalid argument. `beta` must be a positive number. Value: `' + beta + '`.' ); 48 } 49 return null; 50 } 51 52 53 // EXPORTS // 54 55 module.exports = validate;