---
name: "PGAFitness"
section: "1"
platform: "linux"
package: "pgapack"
version: "1.1.1-3"
release: "Debian 8 (Jessie)"
platforms: ["linux"]
url: "https://new.carta.tech/PGAFitness"
---

# PGAFitness(1)

Maps the user's evaluation function value to a fitness value.

## NAME

PGAFitness - Maps the user's evaluation function value to a fitness value.

## DESCRIPTION

First, the user's evaluation function value is translated to all positive values if any are negative.  Next, this positive sequence is translated to a maximization problem if the user's optimization direction was minimization. This positive sequence is then mapped to a fitness value using linear ranking, linear normalization fitness, or the identity (i.e., the evaluation function value).  This routine is usually used after PGAEvaluate is called.

## INPUT PARAMETERS

- ctx

  \- context variable

- pop

  \- symbolic constant of the population to calculate fitness for

## OUTPUT PARAMETERS

- none

  ## SYNOPSIS

```
#include "pgapack.h"
void  PGAFitness(ctx, popindex)
PGAContext *ctx
int popindex
```

## LOCATION

fitness.c

## EXAMPLE

```
Example:
Calculate the fitness of all strings in population PGA_NEWPOP after
calling PGAEvaluate to calculate the strings evaluation value.
double energy(PGAContext *ctx, int p, int pop);
PGAContext *ctx;
:
PGAEvaluate(ctx, PGA_NEWPOP, energy);
PGAFitness (ctx, PGA_NEWPOP);
```