r2p_nest: Row to Pair Nested Transformation

In mintyr: Streamlined Data Processing Tools for Genomic Selection

Row to Pair Nested Transformation

Description

A sophisticated data transformation tool for performing row pair conversion and creating nested data structures with advanced configuration options.

Usage

r2p_nest(data, rows2bind, by, nest_type = "dt")

Arguments

data	Input ⁠data frame⁠ or ⁠data table⁠ Must contain valid columns for transformation Supports multiple data types
rows2bind	Row binding specification Can be a character column name Can be a numeric column index Must be a single column identifier
by	Grouping specification for nested pairing Can be a character vector of column names Can be a numeric vector of column indices Must specify at least one column Supports multi-column transformation
nest_type	Output nesting format "dt": Returns nested ⁠data table⁠ (default) "df": Returns nested ⁠data frame⁠

Details

Advanced Transformation Mechanism:

1. Input validation and preprocessing

2. Dynamic column identification

3. Flexible row pairing across specified columns

4. Nested data structure generation

Transformation Process:

• Validate input parameters and column specifications

• Convert numeric indices to column names if necessary

• Reshape data from wide to long format

• Perform column-wise nested transformation

• Generate final nested structure

Column Specification:

• Supports both column names and numeric indices

• Numeric indices must be within valid range (1 to ncol)

• Column names must exist in the dataset

• Flexible specification for both rows2bind and by parameters

Value

⁠data table⁠ containing nested transformation results

• Includes name column identifying source columns

• Contains data column storing nested data structures

Note

Key Operation Constraints:

• Requires non-empty input data

• Column specifications must be valid (either names or indices)

• By parameter must specify at least one column

• Low computational overhead

See Also

• data.table::melt() Long format conversion

• data.table::dcast() Wide format conversion

• base::rbind() Row binding utility

• c2p_nest() Column to pair nested transformation

Examples

# Example 1: Row-to-pairs nesting with column names
r2p_nest(
  mtcars,                     # Input mtcars dataset
  rows2bind = "cyl",          # Column to be used as row values
  by = c("hp", "drat", "wt")  # Columns to be transformed into pairs
)
# Returns a nested data.table where:
# - name: variable names (hp, drat, wt)
# - data: list column containing data.tables with rows grouped by cyl values

# Example 2: Row-to-pairs nesting with numeric indices
r2p_nest(
  mtcars,                     # Input mtcars dataset
  rows2bind = 2,              # Use 2nd column (cyl) as row values
  by = 4:6                    # Use columns 4-6 (hp, drat, wt) for pairs
)
# Returns a nested data.table where:
# - name: variable names from columns 4-6
# - data: list column containing data.tables with rows grouped by cyl values

mintyr documentation built on April 4, 2025, 2:56 a.m.