histogram

Syntax

histogram(X, [bins=10], [range], [density=false], [weights])

Details

Compute the histogram of a dataset.

Arguments

X is a numeric vector indicating the input data.

bins (optional) is a positive integer or a strictly increasing numeric vector：

A positive integer specifies the number of bins of equal width. The default value is 10.
A numeric vector specifies the bin edges, including the rightmost edge.

range (optional) is a pair or a numeric vector of length 2, indicating the lower and upper range of the bins. Values outside the range are ignored. The default value is [X.min(), X.max()].

density (optional) is a boolean value:

false (default): the result will contain the number of samples in each bin.
true: the result is the value of the probability density function at the bin, normalized such that the integral over the range is 1.

weights (optional) is a numeric vector of the same length as X, representing the weight of each sample. Note that when density is false, the return value is the weighted counts.

Return Value

A dictionary containing the following key-value pairs:

H: The values of the histogram. See density and weights for a description of the possible semantics.
edges: the bin edges.

Examples

bins can be an integral scalar.

X = [3,4,5,6,7,8,9]
bins = 3
histogram(X, bins)
/*
H->[2,2,3]
edges->[3,5,7,9]
*/

bins can be a numeric vector.

X = [3,4,5,6,7,8,9]
bins = [3,6,9]
histogram(X, bins)
/*
H->[3,4]
edges->[3,6,9]
*/

range limits the lower and upper bounds of the bins.

X = [3,4,5,6,7,8,9]
bins = [3,6,9]
range = [4,8]
histogram(X, bins, range)
/*
H->[2,3]
edges->[3,6,9]
*/

If density is true, the result is the value of the probability density function at the bin.

X = [3,4,5,6,7,8,9]
bins = [3,6,9]
range = [4,8]
histogram(X, bins, range, true)
/*
H->[0.133333333333333,0.2]
edges->[3,6,9]
*/

weights specifies the weight for each sample.

X = [3,4,5,6,7,8,9]
bins = [3,6,9]
weights = [2,2,5,5,1,2,3]
histogram(X, bins, , false, weights)
/*
H->[9,11]
edges->[3,6,9]
*/