Write a NumPy program to compute the mean, standard deviation, and variance of a given array along the second axis.
From Wikipedia: There are several kinds of means in various branches of mathematics (especially statistics).
For a data set, the arithmetic mean, also called the mathematical expectation or average, is the central value of a discrete set of numbers: specifically, the sum of the values divided by the number of values. The arithmetic mean of a set of numbers x1, x2, ....., xnx1, x2, ....., xn is typically denoted by x¯x¯, pronounced "xx bar". If the data set were based on a series of observations obtained by sampling from a statistical population, the arithmetic mean is the sample mean (denoted x¯x¯) to distinguish it from the mean of the underlying distribution.
In probability and statistics, the population mean, or expected value, are a measure of the central tendency either of a probability distribution or of the random variable characterized by that distribution. In the case of a discrete probability distribution of a random variable XX, the mean is equal to the sum over every possible value weighted by the probability of that value; that is, it is computed by taking the product of each possible value xx of XX and its probability p(x)px, and then adding all these products together, giving μ = ∑xp(x)μ = ∑xpx. An analogous formula applies to the case of a continuous probability distribution. Not every probability distribution has a defined mean; see the Cauchy distribution for an example. Moreover, for some distributions the mean is infinite.