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hist!

hist!(counts, v, e) -> e, counts

Compute the histogram of v, using a vector/range e as the edges for the bins. This function writes the resultant counts to a pre-allocated array counts.

Examples

1. Compute and store histogram counts:

   julia> counts = zeros(Int, 5);  # Pre-allocate array for counts
   julia> v = [1.2, 2.4, 3.6, 1.2, 4.8, 2.4, 3.6, 4.8];
   julia> edges = [0, 2, 4, 6];  # Bins edges
   julia> hist!(counts, v, edges)
   4-element Array{Int64,1}:
   2
   2
   2
   2

   This example computes the histogram counts of the elements in v using the specified bin edges edges and stores the counts in the pre-allocated counts array.

2. Update histogram counts with new data:

   julia> counts = zeros(Int, 4);  # Pre-allocate array for counts
   julia> v = [1, 2, 3, 4, 1, 2, 3, 4];
   julia> edges = [0, 1, 2, 3, 4];  # Bins edges
   julia> hist!(counts, v, edges)
   4-element Array{Int64,1}:
   2
   2
   2
   2
   
   julia> new_data = [1, 2, 3, 4];
   julia> hist!(counts, new_data, edges)
   4-element Array{Int64,1}:
   4
   4
   4
   4

   In this example, the hist! function is called twice. The first call computes the histogram counts of the initial data, and the second call updates the counts with new data. The counts array is pre-allocated to store the results.

Common mistake example:

julia> counts = zeros(Int, 5);
julia> v = [1, 2, 3, 4, 5];
julia> edges = [0, 2, 4, 6];
julia> hist!(counts, v, edges)
ERROR: DimensionMismatch("destination array must have the same length as source array")

In this example, the counts array is not correctly pre-allocated to match the number of bins defined by the edges array. It's important to ensure that the counts array has the appropriate length to store the histogram results.

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