raw_moment

Calculates the raw moment.

Syntax

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raw_moment(x, k)

Description

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m = raw_moment(x, k)

Calculates the k-th raw moment of all the observations.

That is,

where $x_i,i=1,2,\cdots ,n$$x_i,i=1,2,\cdots,n$ represents the $i$$i$-th observed value.

Examples

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>>> from OpenHA.processing.feature import raw_moment
>>> import numpy as np

>>> x = np.array([0, 1, 2, 3, 4])
>>> print(raw_moment(x, 2))

# = (0^2 + 1^2 + 2^2 + 3^2 + 4^2) / 5
# = (0 + 1 + 4 + 9 + 16) / 5
# = 30 / 5
6

Input Arguments

x —— The value of observations, specified as an array of N-D array of length n.

For an n-by-m array, it indicates n observations with m features.

k —— Order of raw moment, specified as a positive integer scalar.

Properties of Arguments