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@stdlib/array

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{{alias}}( x, searchElement, fromIndex, equalNaNs ) Returns the index of the last element which equals a provided search element. If provided an array-like object having a `lastIndexOf` method and `equalNaNs` is `false`, the function defers execution to that method and assumes that the method has the following signature: x.lastIndexOf( searchElement, fromIndex ) If provided an array-like object without a `lastIndexOf` method or if `equalNaNs` is `true`, the function performs a linear scan and returns immediately upon finding a match. If unable to find an element which equals a provided search element, the function returns -1. The function scans an input array from the starting index to the beginning of the array (i.e., backward). Parameters ---------- x: ArrayLikeObject Input array. searchElement: any Search element. fromIndex: integer Starting index (inclusive). If less than zero, the starting index is resolved relative to the last array element, with the last array element corresponding to `fromIndex = -1`. equalNaNs: boolean Boolean indicating whether NaNs should be considered equal. Returns ------- out: integer Index or -1. Examples -------- > var out = {{alias}}( [ 1, 3, 3, 4 ], 3, 3, false ) 2 See Also --------