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Macros | Functions
shuffle-def.h File Reference

Shuffle preprocessor metaprogram. More...

`#include "host.h"`
`#include "random.h"`
`#include <assert.h>`

## Macros

#define | VL_SHUFFLE_array VL_SHUFFLE_type*
#define | VL_SHUFFLE_prefix ShufflePrefix
#define | VL_SHUFFLE_type ShuffleType
#define | VL_SHUFFLE_array ShuffleType*

## Functions

void | VL_SHUFFLE_swap (VL_SHUFFLE_array array, vl_uindex indexA, vl_uindex indexB)
| Swap two array elements. More...
void | VL_SHUFFLE_shuffle (VL_SHUFFLE_array array, vl_size size, VlRand *rand)
| Shuffle. More...

## Detailed Description

Author
  Andrea Vedaldi

Todo:
  large array compatibility.

## Macro Definition Documentation

#define VL_SHUFFLE_array VL_SHUFFLE_type*

Data type of the shuffle container

#define VL_SHUFFLE_array ShuffleType*

Data type of the shuffle container

#define VL_SHUFFLE_prefix ShufflePrefix

Prefix of the shuffle functions

#define VL_SHUFFLE_type ShuffleType

Data type of the shuffle elements

## Function Documentation

void VL_SHUFFLE_shuffle | ( | VL_SHUFFLE_array | array,
|  | vl_size | size,
|  | VlRand * | rand
| ) |  |

inline

Parameters

  array | (in/out) pointer to the array.
  size | size of the array.
  rand | random number generator to use.

The function randomly permutes the array.

void VL_SHUFFLE_swap | ( | VL_SHUFFLE_array | array,
|  | vl_uindex | indexA,
|  | vl_uindex | indexB
| ) |  |

inline

Parameters

  array | shuffle array.
  indexA | index of the first element to swap.
  indexB | index of the second element to swap.

The function swaps the two elements a and @ b. The function uses a temporary element of type VL_SHUFFLE_type and the copy operator `=`.