cov() function to find the covariance between the columns of the data frame.
corr() function to find the correlation among the columns in the data frame using
rolling() - Pandas
rolling() the function provides the feature of rolling window calculations. The concept of rolling window calculation is most primarily used in signal processing and time-series data. In very simple words we take a window size of k at a time and perform some desired mathematical operation on it. A window of size k means k consecutive values at a time.
expanding() - A common alternative to rolling statistics is to use an expanding window, which yields the value of the statistic with all the data available up to that point in time. These follow a similar interface to .rolling, with the .expanding method returning an Expanding object.
aggregate() - aggregate() function is used to apply some aggregation across one or more columns. Aggregate using callable, string, dict, or list of string/callables. Most frequently used aggregations are:
sum: Return the sum of the values for the requested axis
min: Return the minimum of the values for the requested axis
max: Return the maximum of the values for the requested axis