reduce(op, itr)

reduce(op, itr)

Like reduce(op, v0, itr). This cannot be used with empty collections, except for some special cases (e.g. when op is one of +, *, max, min, &, |) when Julia can determine the neutral element of op.


julia> reduce(-, 1:5)
julia> reduce(+, 1:5)
  1. Calculate the sum of an array:

    julia> arr = [1, 2, 3, 4, 5];
    julia> reduce(+, 0, arr)

    This example uses the reduce function to calculate the sum of all elements in the array arr. The + operator is used as the binary operator, and 0 is the neutral element for addition.

  2. Find the maximum value in a collection:

    julia> collection = [7, 2, 9, 5, 1];
    julia> reduce(maximum, collection)

    Here, the reduce function is used with the maximum function to find the maximum value in the collection.

  3. Concatenate strings in a collection:

    julia> strings = ["Hello", ", ", "world", "!"];
    julia> reduce(*, strings)
    "Hello, world!"

    In this example, the reduce function is used with the * operator to concatenate the strings in the collection.

  4. Handle empty collections with a default value:
    julia> empty_collection = Int[];
    julia> reduce(+, 0, empty_collection)

    When reducing an empty collection, the v0 value (in this case, 0) is returned as the result.

Note: It is recommended to use specialized functions like sum, prod, maximum, etc., when applicable, as they have optimized implementations for specific operations.

See Also

append!, delete!, deleteat!, empty!, endof, filter, filter!, gc, get!, getkey, haskey, insert!, isempty, keys, map, map!, merge, merge!, pop!, prepend!, push!, reduce, resize!, shift!, splice!, unshift!, values,

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