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broadcast

broadcast(f, As...)

Broadcasts the arrays As to a common size by expanding singleton dimensions, and returns an array of the results f(as...) for each position.

Examples

1. Broadcast a function over arrays:

   julia> arr1 = [1, 2, 3];
   julia> arr2 = [4, 5, 6];
   julia> broadcast(+, arr1, arr2)
   3-element Array{Int64,1}:
   5
   7
   9

   This example broadcasts the addition function + over arr1 and arr2, resulting in a new array where each element is the sum of the corresponding elements from arr1 and arr2.

2. Broadcast a function over a scalar and an array:

   julia> scalar = 10;
   julia> arr = [1, 2, 3];
   julia> broadcast(*, scalar, arr)
   3-element Array{Int64,1}:
   10
   20
   30

   Here, the multiplication function * is applied element-wise between the scalar value scalar and each element of the array arr.

3. Broadcast a function over multiple arrays:

   julia> arr1 = [1, 2, 3];
   julia> arr2 = [4, 5, 6];
   julia> arr3 = [7, 8, 9];
   julia> broadcast(-, arr1, arr2, arr3)
   3-element Array{Int64,1}:
   -10
   -11
   -12

   This example broadcasts the subtraction function - over arr1, arr2, and arr3, resulting in a new array where each element is the difference of the corresponding elements from the three arrays.

Common mistake example:

julia> arr1 = [1, 2, 3];
julia> arr2 = [4, 5];
julia> broadcast(+, arr1, arr2)
ERROR: DimensionMismatch("arrays could not be broadcast to a common size")

In this example, the arrays arr1 and arr2 are not compatible for broadcasting because their sizes do not match. It's important to ensure that the arrays being broadcasted have compatible dimensions to avoid such errors.

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