Teradata Package for R Function Reference | 17.20 - RandomProjectionMinComponents - Teradata Package for R - Look here for syntax, methods and examples for the functions included in the Teradata Package for R.

Teradata® Package for R Function Reference

Deployment
VantageCloud
VantageCore
Edition
Enterprise
IntelliFlex
VMware
Product
Teradata Package for R
Release Number
17.20
Published
March 2024
Language
English (United States)
Last Update
2024-05-03
dita:id
TeradataR_FxRef_Enterprise_1720
Product Category
Teradata Vantage

RandomProjectionMinComponents

Description

The td_random_projection_min_components_sqle() function calculates "num_components" required for applying td_random_projection_fit_sqle() on the given dataset for the specified "epsilon" (distortion) parameter value. The function estimates the minimum value of the "num_components" argument in the td_random_projection_fit_sqle() function for a given dataset. The function uses the Johnson-Lindenstrauss Lemma algorithm to calculate the value.

Usage

  td_random_projection_min_components_sqle (
      data = NULL,
      target.columns = NULL,
      epsilon = 0.1,
      ...
  )

Arguments

data

Required Argument.
Specifies the input tbl_teradata.
Types: tbl_teradata

target.columns

Required Argument.
Specifies the name(s) of the column(s) in "data" for random projection.
Types: character OR vector of Strings (character)

epsilon

Optional Argument.
Specifies a value to control distortion introduced while projecting the data to a lower dimension. The amount of distortion increases if you increase the value. Allowed Value is between 0 and 1.
Default Value: 0.1
Types: float OR integer

...

Specifies the generic keyword arguments SQLE functions accept.
Below are the generic keyword arguments:

persist:
Optional Argument.
Specifies whether to persist the results of the
function in a table or not. When set to TRUE, results are persisted in a table; otherwise, results are garbage collected at the end of the session.
Default Value: FALSE
Types: logical

volatile:
Optional Argument.
Specifies whether to put the results of the
function in a volatile table or not. When set to TRUE, results are stored in a volatile table, otherwise not.
Default Value: FALSE
Types: logical

Function allows the user to partition, hash, order or local order the input data. These generic arguments are available for each argument that accepts tbl_teradata as input and can be accessed as:

  • "<input.data.arg.name>.partition.column" accepts character or vector of character (Strings)

  • "<input.data.arg.name>.hash.column" accepts character or vector of character (Strings)

  • "<input.data.arg.name>.order.column" accepts character or vector of character (Strings)

  • "local.order.<input.data.arg.name>" accepts logical

Note:
These generic arguments are supported by tdplyr if the underlying SQL Engine function supports, else an exception is raised.

Value

Function returns an object of class "td_random_projection_min_components_sqle" which is a named list containing object of class "tbl_teradata".
Named list member(s) can be referenced directly with the "$" operator using the name(s):result

Examples

  
    
    # Get the current context/connection.
    con <- td_get_context()$connection
    
    # Load the example data.
    loadExampleData("tdplyr_example", "stock_movement")
    
    # Create tbl_teradata object.
    stock_movement <- tbl(con, "stock_movement")
    
    # Check the list of available analytic functions.
    display_analytic_functions()
    
    # Example 1 : Calculate the minimum number of components required
    #             for applying td_random_projection_fit_sqle().
    RandomProjectionMinComponents_out <- td_random_projection_min_components_sqle(
                                                            data = stock_movement,
                                                            target.columns = "1:")
    
    # Print the result.
    print(RandomProjectionMinComponents_out$result)