README.md (2248B)
1 <!-- 2 3 @license Apache-2.0 4 5 Copyright (c) 2018 The Stdlib Authors. 6 7 Licensed under the Apache License, Version 2.0 (the "License"); 8 you may not use this file except in compliance with the License. 9 You may obtain a copy of the License at 10 11 http://www.apache.org/licenses/LICENSE-2.0 12 13 Unless required by applicable law or agreed to in writing, software 14 distributed under the License is distributed on an "AS IS" BASIS, 15 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16 See the License for the specific language governing permissions and 17 limitations under the License. 18 19 --> 20 21 # isNegativeInteger 22 23 > Test if a finite [double-precision floating-point number][ieee754] is a negative integer. 24 25 <section class="usage"> 26 27 ## Usage 28 29 ```javascript 30 var isNegativeInteger = require( '@stdlib/math/base/assert/is-negative-integer' ); 31 ``` 32 33 #### isNegativeInteger( x ) 34 35 Tests if a finite [double-precision floating-point number][ieee754] is a negative `integer`. 36 37 ```javascript 38 var bool = isNegativeInteger( -1.0 ); 39 // returns true 40 41 bool = isNegativeInteger( 0.0 ); 42 // returns false 43 44 bool = isNegativeInteger( 10.0 ); 45 // returns false 46 ``` 47 48 </section> 49 50 <!-- /.usage --> 51 52 <section class="notes"> 53 54 ## Notes 55 56 - The function assumes a **finite** `number`. If provided negative `infinity`, the function will return `true`, when, in fact, the result is undefined. If `x` can be `infinite`, wrap the implementation as follows: 57 58 ```javascript 59 function check( x ) { 60 return ( 61 x > -Infinity && 62 isNegativeInteger( x ) 63 ); 64 } 65 66 var bool = check( -Infinity ); 67 // returns false 68 ``` 69 70 </section> 71 72 <!-- /.notes --> 73 74 <section class="examples"> 75 76 ## Examples 77 78 <!-- eslint no-undef: "error" --> 79 80 ```javascript 81 var isNegativeInteger = require( '@stdlib/math/base/assert/is-negative-integer' ); 82 83 var bool = isNegativeInteger( -5.0 ); 84 // returns true 85 86 bool = isNegativeInteger( 0.0 ); 87 // returns false 88 89 bool = isNegativeInteger( 1.0 ); 90 // returns false 91 92 bool = isNegativeInteger( -3.14 ); 93 // returns false 94 95 bool = isNegativeInteger( NaN ); 96 // returns false 97 ``` 98 99 </section> 100 101 <!-- /.examples --> 102 103 <section class="links"> 104 105 [ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985 106 107 </section> 108 109 <!-- /.links -->