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    @stdlib/iter-linspace
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    0.0.6 • Public • Published

    iterLinspace

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    Create an iterator which returns evenly spaced numbers over a specified interval.

    Installation

    npm install @stdlib/iter-linspace

    Usage

    var iterLinspace = require( '@stdlib/iter-linspace' );

    iterLinspace( start, stop[, N] )

    Returns an iterator which returns evenly spaced numbers over a specified interval.

    var it = iterLinspace( 0, 99 );
    // returns <Object>
    
    var v = it.next().value;
    // returns 0
    
    v = it.next().value;
    // returns 1
    
    v = it.next().value;
    // returns 2
    
    // ...

    The returned iterator protocol-compliant object has the following properties:

    • next: function which returns an iterator protocol-compliant object containing the next iterated value (if one exists) assigned to a value property and a done property having a boolean value indicating whether the iterator is finished.
    • return: function which closes an iterator and returns a single (optional) argument in an iterator protocol-compliant object.

    By default, the iterator returns 100 values. To return an alternative number of values over the specified interval, provide an N argument.

    var it = iterLinspace( 0, 10, 3 );
    // returns <Object>
    
    var v = it.next().value;
    // returns 0
    
    v = it.next().value;
    // returns 5
    
    v = it.next().value;
    // returns 10
    
    var bool = it.next().done;
    // returns true

    Notes

    • The returned iterator is guaranteed to return the start and stop values. Beware, however, that values between the start and stop are subject to floating-point rounding errors. For example,

      var it = iterLinspace( 0.0, 1.0, 3 );
      // returns <Object>
      
      var v = it.next().value;
      // returns 0
      
      v = it.next().value;
      // returns ~0.5
      
      v = it.next().value;
      // returns 1.0

      where the second iterated value is only guaranteed to be approximately equal to 0.5. If you desire more control over value precision, consider using roundn:

      var roundn = require( '@stdlib/math-base-special-roundn' );
      var iterMap = require( '@stdlib/iter-map' );
      
      function round( v ) {
          return roundn( v, -2 );
      }
      
      // Create an iterator returning values subject to floating-point errors:
      var it1 = iterLinspace( 0.0, 1.0, 21 );
      
      // Create an iterator to round each value to the nearest hundredth:
      var it2 = iterMap( it1, roundn );
      
      // Perform manual iteration...
      var v;
      while ( true ) {
          v = it2.next();
          if ( v.done ) {
              break;
          }
          console.log( v.value );
      }
    • If an environment supports Symbol.iterator, the returned iterator is iterable.

    Examples

    var iterLinspace = require( '@stdlib/iter-linspace' );
    
    // Create a "countdown" iterator:
    var it = iterLinspace( 100, 0, 101 );
    
    // Perform manual iteration...
    var v;
    while ( true ) {
        v = it.next();
        if ( v.done ) {
            break;
        }
        console.log( v.value );
    }

    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.

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    License

    See LICENSE.

    Copyright

    Copyright © 2016-2021. The Stdlib Authors.

    Install

    npm i @stdlib/iter-linspace

    Homepage

    stdlib.io

    DownloadsWeekly Downloads

    142

    Version

    0.0.6

    License

    Apache-2.0

    Unpacked Size

    43.1 kB

    Total Files

    9

    Last publish

    Collaborators

    • stdlib-bot
    • kgryte
    • planeshifter
    • rreusser