datafort_boolean_indexing

DataFort Boolean Indexing Module

This module provides pandas-like boolean indexing/masking functionality. It allows filtering data frames using logical masks created from comparison operations and combined with logical operators.

Features

Boolean masks: Create and manipulate logical masks
Comparison operators: gt, lt, ge, le, eq, ne for real, integer, and character columns
Logical operators: AND, OR, NOT operations on masks
DataFrame filtering: Apply masks to filter data frames (df[mask] style)

Example Usage

use datafort
use datafort_boolean_indexing
type(data_frame) :: df, filtered
type(boolean_mask) :: mask1, mask2, combined

! Create masks using comparison operators
mask1 = gt_real(df, "temperature", 25.0_rk)
mask2 = lt_real(df, "humidity", 60.0_rk)

! Combine masks with logical operators
combined = mask_and(mask1, mask2)

! Filter dataframe
filtered = df_filter(df, combined)

Uses

Derived Types

type, public :: boolean_mask

Boolean mask type for storing logical arrays

Components

Type	Visibility	Attributes		Name		Initial
logical,	private		::	initialized	=	.false.
logical,	private,	dimension(:), allocatable	::	mask
integer,	private		::	size	=	0

Type-Bound Procedures

procedure, public :: destroy => mask_destructor
procedure, public :: get_mask => mask_get
procedure, public :: get_size => mask_get_size
procedure, public :: is_initialized => mask_is_initialized
procedure, public :: new => mask_constructor

Functions

public function contains_character(df, col, substring) result(mask)

Contains substring comparison for character columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
character(len=*),	intent(in)	::	substring

Return Value type(boolean_mask)

public function df_filter(df, mask) result(filtered_df)

Filter data frame using a boolean mask (pandas-like df[mask] operation)

Arguments

Type	Intent	Optional	Attributes		Name
type(data_frame),	intent(in)			::	df
type(boolean_mask),	intent(in)			::	mask

Return Value type(data_frame)

public function eq_character(df, col, value) result(mask)

Equality comparison for character columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
character(len=*),	intent(in)	::	value

Return Value type(boolean_mask)

public function eq_integer(df, col, value) result(mask)

Equality comparison for integer columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
integer(kind=ik),	intent(in)	::	value

Return Value type(boolean_mask)

public function eq_real(df, col, value) result(mask)

Equality comparison for real columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
real(kind=rk),	intent(in)	::	value

Return Value type(boolean_mask)

public function ge_integer(df, col, value) result(mask)

Greater than or equal comparison for integer columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
integer(kind=ik),	intent(in)	::	value

Return Value type(boolean_mask)

public function ge_real(df, col, value) result(mask)

Greater than or equal comparison for real columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
real(kind=rk),	intent(in)	::	value

Return Value type(boolean_mask)

private function get_column_index(df, col) result(col_index)

Get column index from either integer or character input

Arguments

Type	Intent	Optional	Attributes		Name
type(data_frame),	intent(in)			::	df
class(*),	intent(in)			::	col

Return Value integer

public function gt_integer(df, col, value) result(mask)

Greater than comparison for integer columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
integer(kind=ik),	intent(in)	::	value

Return Value type(boolean_mask)

public function gt_real(df, col, value) result(mask)

Greater than comparison for real columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
real(kind=rk),	intent(in)	::	value

Return Value type(boolean_mask)

public function le_integer(df, col, value) result(mask)

Less than or equal comparison for integer columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
integer(kind=ik),	intent(in)	::	value

Return Value type(boolean_mask)

public function le_real(df, col, value) result(mask)

Less than or equal comparison for real columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
real(kind=rk),	intent(in)	::	value

Return Value type(boolean_mask)

public function lt_integer(df, col, value) result(mask)

Less than comparison for integer columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
integer(kind=ik),	intent(in)	::	value

Return Value type(boolean_mask)

public function lt_real(df, col, value) result(mask)

Less than comparison for real columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
real(kind=rk),	intent(in)	::	value

Return Value type(boolean_mask)

public function mask_and(mask1, mask2) result(result_mask)

Logical AND operation on two masks

Arguments

Type	Intent	Optional	Attributes		Name
type(boolean_mask),	intent(in)			::	mask1
type(boolean_mask),	intent(in)			::	mask2

Return Value type(boolean_mask)

private function mask_get(this) result(logical_array)

Get the logical array from the mask

Arguments

Type	Intent	Optional	Attributes		Name
class(boolean_mask),	intent(in)			::	this

Return Value logical, dimension(:), allocatable

private pure function mask_get_size(this) result(size)

Get the size of the mask

Arguments

Type	Intent	Optional	Attributes		Name
class(boolean_mask),	intent(in)			::	this

Return Value integer

private pure function mask_is_initialized(this) result(is_init)

Check if mask is initialized

Arguments

Type	Intent	Optional	Attributes		Name
class(boolean_mask),	intent(in)			::	this

Return Value logical

public function mask_not(mask) result(result_mask)

Logical NOT operation on a mask

Arguments

Type	Intent	Optional	Attributes		Name
type(boolean_mask),	intent(in)			::	mask

Return Value type(boolean_mask)

public function mask_or(mask1, mask2) result(result_mask)

Logical OR operation on two masks

Arguments

Type	Intent	Optional	Attributes		Name
type(boolean_mask),	intent(in)			::	mask1
type(boolean_mask),	intent(in)			::	mask2

Return Value type(boolean_mask)

public function ne_character(df, col, value) result(mask)

Not equal comparison for character columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
character(len=*),	intent(in)	::	value

Return Value type(boolean_mask)

public function ne_integer(df, col, value) result(mask)

Not equal comparison for integer columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
integer(kind=ik),	intent(in)	::	value

Return Value type(boolean_mask)

public function ne_real(df, col, value) result(mask)

Not equal comparison for real columns

Arguments

Type	Intent		Name
type(data_frame),	intent(in)	::	df
class(*),	intent(in)	::	col
real(kind=rk),	intent(in)	::	value

Return Value type(boolean_mask)

Subroutines

private subroutine mask_constructor(this, logical_array)

Initialize a boolean mask from a logical array

Arguments

Type	Intent	Optional	Attributes		Name
class(boolean_mask),	intent(inout)			::	this
logical,	intent(in),		dimension(:)	::	logical_array

private subroutine mask_destructor(this)

Destroy a boolean mask and free memory

Arguments

Type	Intent	Optional	Attributes		Name
class(boolean_mask),	intent(inout)			::	this

datafort_boolean_indexing Module

Contents

Derived Types

Functions

Subroutines

Features

Example Usage

Uses

Derived Types

type, public :: boolean_mask

Components

Type-Bound Procedures

Functions

public function contains_character(df, col, substring) result(mask)

Arguments

Return Value type(boolean_mask)

public function df_filter(df, mask) result(filtered_df)

Arguments

Return Value type(data_frame)

public function eq_character(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function eq_integer(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function eq_real(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function ge_integer(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function ge_real(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

private function get_column_index(df, col) result(col_index)

Arguments

Return Value integer

public function gt_integer(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function gt_real(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function le_integer(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function le_real(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function lt_integer(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function lt_real(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function mask_and(mask1, mask2) result(result_mask)

Arguments

Return Value type(boolean_mask)

private function mask_get(this) result(logical_array)

Arguments

Return Value logical, dimension(:), allocatable

private pure function mask_get_size(this) result(size)

Arguments

Return Value integer

private pure function mask_is_initialized(this) result(is_init)

Arguments

Return Value logical

public function mask_not(mask) result(result_mask)

Arguments

Return Value type(boolean_mask)

public function mask_or(mask1, mask2) result(result_mask)

Arguments

Return Value type(boolean_mask)

public function ne_character(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function ne_integer(df, col, value) result(mask)

Arguments

Return Value type(boolean_mask)

public function ne_real(df, col, value) result(mask)