Teradata Package for Python Function Reference | 20.00 - shiftleft - 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 - 20.00
- Deployment
- VantageCloud
- VantageCore
- Edition
- Enterprise
- IntelliFlex
- VMware
- 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_Enterprise_2000
- Product Category
- Teradata Vantage
- teradataml.dataframe.sql.DataFrameColumn.shiftleft = shiftleft(bit_mask)
- DESCRIPTION:
Function returns the integer or byte value of column shifted by the specified
number of bits ("bit_mask") to the left. The bits in the most significant
positions are lost, and the bits in the least significant positions are
filled with zeros.
PARAMETERS:
bit_mask:
Required Argument.
Specifies a ColumnExpression of an integer column or an integer literal
indicating the number of bit positions to shift.
Notes:
1. If "bit_mask" is equal to zero, then the function returns integer or byte
value of column unchanged.
2. If "bit_mask" is negative, then the function shifts the bits to the right
instead of the left.
3. If integer or byte value of column and/or "bit_mask" are NULL, then the
function returns NULL.
4. The scope of the shift operation is bounded by the size of the integer or byte
value of column. Specifying a shift that is outside the range of integer or byte
value of column results in an error.
Format of a ColumnExpression of a column: '<dataframe>.<dataframe_column>'.
Types: ColumnExpression, int
RAISES:
TypeError, ValueError, TeradataMlException
RETURNS:
DataFrameColumn
EXAMPLES:
# Load the data to run the example.
>>> load_example_data("dataframe", "bytes_table")
# Create a DataFrame on 'bytes_table' table.
>>> df = DataFrame("bytes_table")
>>> print(df)
byte_col varbyte_col blob_col
id_col
2 b'61' b'616263643132' b'6162636431323233'
1 b'62' b'62717765' b'3331363136323633'
0 b'63' b'627A7863' b'3330363136323633'
# Example1: Shifts values in "varbyte_col" column to left by 3 bits and
# pass it as input to DataFrame.assign().
>>> res_df = df.assign(col= df.varbyte_col.shiftleft(3))
>>> print(res_df)
byte_col varbyte_col blob_col col
id_col
2 b'61' b'616263643132' b'6162636431323233' b'B131B218990'
1 b'62' b'62717765' b'3331363136323633' b'138BBB28'
0 b'63' b'627A7863' b'3330363136323633' b'13D3C318'