Frame covariance¶
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covariance
(self, data_column_names)¶ Calculate covariance for exactly two columns.
Parameters: data_column_names : list
The names of two columns from which to compute the covariance.
Returns: : float64
Covariance of the two columns.
This method applies only to columns containing numerical data.
Examples
Consider Frame my_frame, which contains the data
>>> my_frame.inspect() [#] idnum x1 x2 x3 x4 =============================== [0] 0 1.0 4.0 0.0 -1.0 [1] 1 2.0 3.0 0.0 -1.0 [2] 2 3.0 2.0 1.0 -1.0 [3] 3 4.0 1.0 2.0 -1.0 [4] 4 5.0 0.0 2.0 -1.0
my_frame.covariance computes the covariance on the pair of columns provided.
>>> my_frame.covariance(["x1", "x2"]) [===Job Progress===]
-2.5>>> my_frame.covariance(["x1", "x4"]) [===Job Progress===]
0.0>>> my_frame.covariance(["x2", "x3"]) [===Job Progress===]
-1.5