Glyph remote

glyph-remote is shipped together with the glyph package. After installation, the glyph-remote command is available at the command line.

Concept

With glyph-remote the separation between optimization method and optimization task is made easy. glyph-remote runs multi IO symbolic regression and sends candidate solution via ZeroMQ to an experiment controller for assessment. Every hyper-parameter used is assessable and fully configurable.

Overview

To the right the optimization method is represented. The GP program can be seen as a black box which is only accessible by the specified interface. To the left a single experiment plus an event handler is depicted. The latter glues optimization method and task together and needs to understand the communication protocol defined in

Currently we use client server sockets for glyph remote. The user needs to implement the zmq.REP socket.

Communication protocol

The communication is encoded in json. A message is a json object with two members:

{
    "action": "value",
    "payload": "value",
}

The possible action values are:

Action name Payload Expected return Value
CONFIG config settings
EXPERIMENT list of expressions list of fitness value(s)
SHUTDOWN

The config action is performed prior to the evolutionary loop. Entering the loop, for every discovered solution an experiment action will be requested. Since most experiments have an intermediate compiling step, expressions will come in chunks. You can configure optional caching for re-discovered solutions. The shutdown action will let the experiment program know that the gp loop is finished and you can safely stop the hardware.

Config

See Configuration section.

Experiment

The experiment request expects a fitness value for each expression:

{
    "fitness": ["value0", "value1", ...],
}

Shutdown

YOu can properly shut down the experiment hardware.

Configuration

For a full list of configuration options and their default values type glyph-remote --help.

All hyper-parameters and algorithms used have default values. You have three options to set parameters:

  • use the command line interface
  • read from file (using --cfile myfile.yaml)
  • request from event handler (using --remote)

At cli, options are specified using --key value. The configuration file has to be written in yaml, i.e.

key: value

The event handler should send back a similar json array

{
  "key": "value",
}

It is mandatory to provide a information about the primitives you want to use. The value of the “primitives” key is again a json/yaml list specifying name: arity pairs. Arities greater one are functions, equal to one are variables and -1 is reserved for symbolic constants.

{
  "primitives":
  {
    "add": 2,
    "x": 0,
  },
}