🎛️ Parameter file format

Parameter files (.params) describe the configuration space: which parameters exist, their domains, defaults, conditional activation, and forbidden combinations.

RamParILS supports the discrete parameter syntax used by the original Ruby ParamILS implementation. Continuous ranges and other ParamILS variants are not supported; enumerate every allowed value explicitly.

🔢 Discrete parameters

name {val1, val2, val3, ...} [default]

Example:

alpha {1.01, 1.066, 1.126, 1.189, 1.256, 1.326, 1.4} [1.189]
rho   {0, 0.17, 0.5, 1}                               [0.5]

Values are always strings. Numeric values are parsed by the target algorithm.

🔀 Conditional parameters

A conditional parameter is only active (included in the command line) when its parent has a specific value:

child {val1, val2} [default] | parent in {allowed1, allowed2}

Example:

noise_type {random, walk} [random]
noise_param {0.0, 0.1, 0.5} [0.1] | noise_type in {walk}

noise_param is only passed to the algorithm when noise_type = walk. Otherwise it is omitted from the command line.

⛔ Forbidden combinations

A forbidden combination prevents specific joint assignments from being evaluated:

{param1=val1, param2=val2, ...}

Example:

{alpha=1.01, rho=0}

Any configuration where alpha=1.01 and rho=0 simultaneously is skipped during search.

💬 Comments

Lines starting with # and trailing #... are ignored:

# This is a comment
alpha {1.01, 1.189} [1.189]   # inline comment

🧩 Full example

# SAPS parameters
alpha {1.01, 1.066, 1.126, 1.189, 1.256, 1.326, 1.4} [1.189]
rho   {0, 0.17, 0.5, 1}                               [0.5]
ps    {0.0, 0.01, 0.05, 0.1, 0.2, 0.5}                [0.1]
wp    {0.0, 0.01, 0.05, 0.1, 0.2}                     [0.03]

# Forbidden: degenerate case
{alpha=1.01, rho=0}