Teradata Package for Python Function Reference on VantageCloud Lake - regr_intercept - Teradata Package for Python - Look here for syntax, methods and examples for the functions included in the Teradata Package for Python.
Teradata® Package for Python Function Reference on VantageCloud Lake
- Deployment
- VantageCloud
- Edition
- Lake
- Product
- Teradata Package for Python
- Release Number
- 20.00.00.03
- Published
- December 2024
- ft:locale
- en-US
- ft:lastEdition
- 2024-12-19
- dita:id
- TeradataPython_FxRef_Lake_2000
- Product Category
- Teradata Vantage
- teradataml.dataframe.sql.DataFrameColumn.regr_intercept = regr_intercept(expression)
- DESCRIPTION:
Function returns the intercept of the univariate linear regression line
through all non-null data pairs of the dependent and independent variable
arguments. The intercept is the point at which the regression line through
the non-null data pairs in the sample intersects the ordinate, or y-axis,
of the graph. The plot of the linear regression on the variables is used to
predict the behavior of the dependent variable from the change in the
independent variable. There can be a strong nonlinear relationship between
independent and dependent variables, and the computation of the simple linear
regression between such variable pairs does not reflect such a relationship.
The function considers ColumnExpression as a dependent variable and "expression"
as an independent variable.
PARAMETERS:
expression:
Required Argument.
Specifies a ColumnExpression of a column or name of the column or a
literal representing an independent variable for the regression.
An independent variable is something that is varied under your control
to test the behavior of another variable.
Types: ColumnExpression OR int OR float OR str
RETURNS:
ColumnExpression, also known as, teradataml DataFrameColumn
NOTES:
* One must use DataFrame.assign() when using the aggregate functions on
ColumnExpression, also known as, teradataml DataFrameColumn.
* One should always use "drop_columns=True" in DataFrame.assign(), while
running the aggregate operation on teradataml DataFrame.
* "drop_columns" argument in DataFrame.assign() is ignored, when aggregate
function is operated on DataFrame.groupby().
RAISES:
RuntimeError - If column does not support the aggregate operation.
EXAMPLES:
# Load the data to run the example.
>>> load_example_data("dataframe", "admissions_train")
>>>
# Create a DataFrame on 'admissions_train' table.
>>> admissions_train = DataFrame("admissions_train")
>>> admissions_train
masters gpa stats programming admitted
id
22 yes 3.46 Novice Beginner 0
36 no 3.00 Advanced Novice 0
15 yes 4.00 Advanced Advanced 1
38 yes 2.65 Advanced Beginner 1
5 no 3.44 Novice Novice 0
17 no 3.83 Advanced Advanced 1
34 yes 3.85 Advanced Beginner 0
13 no 4.00 Advanced Novice 1
26 yes 3.57 Advanced Advanced 1
19 yes 1.98 Advanced Advanced 0
>>>
# Example 1: Calculate the intercept of the "gpa" column (independent variable) with
# "admitted" column (dependent variable).
# Execute regr_intercept() using teradataml DataFrameColumn to generate the ColumnExpression.
>>> regr_intercept_column = admissions_train.admitted.regr_intercept(admissions_train.gpa)
# Pass the generated ColumnExpression to DataFrame.assign(), to run and produce the result.
>>> df = admissions_train.assign(True, regr_intercept_=regr_intercept_column)
>>> df
regr_intercept_
0 0.724144
>>>
# Example 2: Calculate the intercept of the "gpa" column (independent variable) with
# "admitted" column (dependent variable) for each
# level of programming.
# Note:
# When assign() is run after DataFrame.groupby(), the function ignores
# the "drop_columns" argument.
# Execute regr_intercept() using teradataml DataFrameColumn to generate the ColumnExpression.
>>> regr_intercept_column = admissions_train.admitted.regr_intercept(admissions_train.gpa)
# Pass the generated ColumnExpression to DataFrame.assign(), to run and produce the result.
>>> df = admissions_train.groupby("programming").assign(regr_intercept_=regr_intercept_column)
>>> df
programming regr_intercept_
0 Advanced -0.626557
1 Novice 1.000091
2 Beginner 2.566361
>>>