# propeller.problems.PSB2.paired-digits documentation

## Generated by Codox

# Propeller 0.3.2

# propeller.problems.PSB2.paired-digits

PAIRED DIGITS from PSB2

Given a string of digits, return the sum of the digits whose following digit is the same.

Source: https://arxiv.org/pdf/2106.06086.pdf

### -main

`(-main & args)`

Runs the top-level genetic programming function, giving it a map of arguments with defaults that can be overridden from the command line or through a passed map.

### error-function

`(error-function argmap data individual)`

Finds the behaviors and errors of an individual: Error is 0 if the value and the program’s selected behavior match, or 1 if they differ, or 1000000 if no behavior is produced. The behavior is here defined as the final top item on the INTEGER stack.

### instructions

Stack-specific instructions, input instructions, close, and constants

### random-char

`(random-char)`

Random character of 0-9

### random-int

`(random-int)`

Random integer between -100 and 100

### train-and-test-data

Data taken from https://zenodo.org/record/5084812