OpenFTS Documentation

OpenFTS is a high performance simulation package in C++11 for performing field-theoretic simulations. OpenFTS is currently under active development by Joshua Lequieu at Drexel University.

Single Diamond Phase

Complex Langevin Simulation

import openfts
fts = openfts.OpenFTS()

fts.cell = openfts.Cell(cell_scale=4.0,cell_lengths=[1.0,1.0,1.0],tilt_factors=[0,0,0],dimension=3,length_unit='Rg')
fts.field_layout = openfts.FieldLayout(npw=[16,16,16], random_seed=1)

scft = openfts.driver.SCFT(dt=5.0,nsteps=4000,output_freq=100,stop_tolerance=1e-05)
scft.field_updater = openfts.field_updater.EMPEC(update_order='simultaneous',adaptive_timestep=False, lambdas=[1.0, 1.0])
fts.driver = scft

chiAB = openfts.model.ChiAB(Nref=1.0,bref=1.0,chiN=20.0)
chiAB.init_fields['mu_plus'] = openfts.init_field.Random(mean=0.0,stdev=10.0)
chiAB.init_fields['mu_minus'] = openfts.init_field.Random(mean=0.0,stdev=10.0)
fts.model = chiAB

diblock = openfts.molecule.PolymerLinearContinuous(alpha=1.0,ds=0.01,nblocks=2,block_fractions=[0.5, 0.5],block_species=['A', 'B'],volume_frac=1.0)
fts.molecules.append(diblock)

fts.operators.append(openfts.operator.Hamiltonian(averaging_type='none'))

fts.species.append(openfts.Species(label='A', b=1.0))
fts.species.append(openfts.Species(label='B', b=1.0))

fts.output = openfts.Output()

fts.run()

Notable features:

• Fully featured python interface

• Calculation via single CPU, multiple CPUs (via OpenMP), Nvidia GPUs (via CUDA) and AMD GPUs (via HIP)

• Double/float support via simple build flags

• Variable Cell SCFT, Complex Langevin simulations, RPA, Gibbs Ensemble

• Automated tools to optimize timesteps

• Linear, comb and star polymer architectures

• Continuous and discrete chain models

• Suports any number of molecules, composed of any number of species, in any monomer sequence

• Multiple field updaters

• Extensive unit/integration tests

• Support for both scaled units (e.g. B,C,E, \(\phi_i\), \(\tilde{a}\), \(\tilde{V}\)) and unscaled units (e.g. \(u_0\), \(\rho_0\), \(l_B\), \(n_i\), a, V)

• Documentation (clearly =D)

Getting Started:

• 1. Building OpenFTS
  • 1.1. Dependencies
  • 1.2. Build Instructions
    • 1.2.1. Problems with building?
    • 1.2.2. Building FFTW
  • 1.3. Build Options
  • 1.4. Running tests
• 2. Running OpenFTS
  • 2.1. OpenFTS as a python module
  • 2.2. OpenFTS as a C++ executable
  • 2.3. Converting between json and python input files
    • 2.3.1. Json to python
    • 2.3.2. Python to json
• 3. Setting up a simulation
• 4. Output files
  • 4.1. Instantaneous species densities
  • 4.2. Instantaneous field configurations
  • 4.3. Scalar operator files
  • 4.4. Field operator files
  • 4.5. Field errors
  • 4.6. Run Status
• 5. FTS Glossary
• 6. Converting to OpenFTS2
  • 6.1. OpenFTS2 (the default)
  • 6.2. OpenFTS1 (depreciated)

Tutorials

• SCFT/FTS Basics
• Mapping from fields to particles
• Improving simulation performance
• Calculating surface tension
• Visualizing field files

Python API

• OpenFTS
• Cell
• Driver
• Field Layout
• Field Updater
• InitField
• Model
• Molecule
• Monitor
• Operator
• Output
• Species
• VariableCell

Python Wrappers

• Gibbs Ensemble
• Timestep Optimization

LEGACY Formalism

• Variable Cell Formalism
• Continuous vs Discrete Chains

Indices and tables

• Index

• Module Index

• Search Page