Cyclopts Basics

Cyclopts is a flexible, plugin framework for defining problem instances, solving those problem instances either locally or on a Condor-enabled High Throughput Computing (HTC) System, and persisting the results. Cyclopts interacts with HDF5 databases.

Nomenclature

Cyclopts uses the following nomenclature

Problem Family

A set of problems that share a similar structure. For example, Cyclus Exchange Graphs all have Nodes, Groups, Arcs, preferences, request and supply constraint quantities, and request and supply constraint coefficients. There is a 1-to-1 mapping between problem families and a collection of instance writing, instance reading, instance execution, and instance solution writing routines.

Problem Species

A subset of a Problem Family that share a definition of parameter space and an instance generation routine that translates a point in parameter space into an instance of the problem with the Problem Family’s structure. An example of a Problem Species for the Exchange Graph problem family is the Fast/Thermal Reactor Request species. There is a 1-to-1 mapping between problem species and a collection of parameter writing and parameter-to-instance translation routines.

Problem Instance

A realization of a Problem Species, conforming to the structure of its Problem Family.

Problem Results

A collection of results from the execution of a Problem Instance

Implementing a New Problem Family

A problem family class must implement the following methods:

• register_tables
• record_inst
• read_inst
• run_inst
• record_soln
• name
• property_table_name

Implementing a New Problem Species

A problem species class must implement the following functions:

• register_tables
• read_space
• record_point
• points
• n_points
• gen_inst
• family
• name

Workflow

After implementing a custom problem family and species, the Cyclopts workflow is as follows.

• Write a parameter space run control file
• cyclopts convert the space into instances
• either
  • cyclopts exec the instances locally or
  • cyclopts condor-submit them, wait for their completion, and cyclopts condor-collect the results
• cyclopts combine the input and output databases
• analyze the results

Tips

Having to declare the family/species module and class names on the command line or in every run control file can be rather annoying. You can set global run control parameters by adding a ~/.cyclopts.rc file to your system. If no other class or module entries are found in either the CLI or declared run control file, this location is searched.