Frame dot_product¶

dot_product(self, left_column_names, right_column_names, dot_product_column_name, default_left_values=None, default_right_values=None)¶

[ALPHA] Calculate dot product for each row in current frame.

Parameters:

Parameters:	left_column_names : list Names of columns used to create the left vector (A) for each row. Names should refer to a single column of type vector, or two or more columns of numeric scalars. right_column_names : list Names of columns used to create right vector (B) for each row. Names should refer to a single column of type vector, or two or more columns of numeric scalars. dot_product_column_name : unicode Name of column used to store the dot product. default_left_values : list (default=None) Default values used to substitute null values in left vector. Default is None. default_right_values : list (default=None) Default values used to substitute null values in right vector. Default is None.

left_column_names : list

Names of columns used to create the left vector (A) for each row. Names should refer to a single column of type vector, or two or more columns of numeric scalars.

right_column_names : list

Names of columns used to create right vector (B) for each row. Names should refer to a single column of type vector, or two or more columns of numeric scalars.

dot_product_column_name : unicode

Name of column used to store the dot product.

default_left_values : list (default=None)

Default values used to substitute null values in left vector. Default is None.

default_right_values : list (default=None)

Default values used to substitute null values in right vector. Default is None.

Calculate the dot product for each row in a frame using values from two equal-length sequences of columns.

Dot product is computed by the following formula:

The dot product of two vectors $A=[a_1, a_2, ..., a_n]$ and $B =[b_1, b_2, ..., b_n]$ is $a_1*b_1 + a_2*b_2 + ...+ a_n*b_n$ . The dot product for each row is stored in a new column in the existing frame.

Notes

If default_left_values or default_right_values are not specified, any null values will be replaced by zeros.

Examples

Calculate the dot product for a sequence of columns in Frame object my_frame:

>>> my_frame.inspect()
[#]  col_0  col_1  col_2  col_3
===============================
[0]      1    0.2     -2      5
[1]      2    0.4     -1      6
[2]      3    0.6      0      7
[3]      4    0.8      1      8

Modify the frame by computing the dot product for a sequence of columns:

 >>> my_frame.dot_product(['col_0','col_1'], ['col_2', 'col_3'], 'dot_product')
 [===Job Progress===]

>>> my_frame.inspect()
[#]  col_0  col_1  col_2  col_3  dot_product
============================================
[0]      1    0.2     -2      5         -1.0
[1]      2    0.4     -1      6          0.4
[2]      3    0.6      0      7          4.2
[3]      4    0.8      1      8         10.4

Calculate the dot product for columns of vectors in Frame object my_frame:

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Frame dot_product¶