External module "utils/reduce/docs/types/index.d"

Export assignment reduce

• reduce(arr: ndarray, initial: any, reducer: Reducer, thisArg?: any): any
• reduce(arr: Collection, initial: any, reducer: ArrayReducer, thisArg?: any): any

• Applies a function against an accumulator and each element in an array and returns the accumulated result.

  Notes

  • The reduction function is provided four arguments:

    • accumulator: accumulated value.
    • value: array element.
    • index: element index.
    • arr: input array.

  • If provided an empty array, the function returns the initial value.

  Parameters

  • arr: ndarray

    input array

  • initial: any

    initial value

  • reducer: Reducer

    reduction function

  • Optional thisArg: any

    reduction function execution context

  Returns any

  accumulated result

  Example

  var naryFunction = require( `@stdlib/utils/nary-function` );
  var add = require( `@stdlib/math/base/ops/add` );
  var array = require( `@stdlib/ndarray/array` );
  
  var opts = {
      'dtype': 'generic'
  };
  var arr = array( [ [ 1, 2, 3 ], [ 4, 5, 6 ] ], opts );
  
  var out = reduce( arr, 0, naryFunction( add, 2 ) );
  // returns 21

• Applies a function against an accumulator and each element in an array and returns the accumulated result.

  Notes

  • The reduction function is provided four arguments:

    • accumulator: accumulated value.
    • value: array element.
    • index: element index.
    • arr: input array.

  • If provided an empty array, the function returns the initial value.

  Parameters

  • arr: Collection

    input array

  • initial: any

    initial value

  • reducer: ArrayReducer

    reduction function

  • Optional thisArg: any

    reduction function execution context

  Returns any

  accumulated result

  Example

  function sum( acc, value ) {
      return acc + value;
  }
  
  var arr = [ 1, 2, 3, 4 ];
  
  var out = reduce( arr, 0, sum );
  // returns 10