Welcome to SPOTPY
A Statistical Parameter Optimization Tool for Python
SPOTPY is a Python framework that enables the use of Computational optimization techniques for calibration, uncertainty and sensitivity analysis techniques of almost every (environmental-) model. The package is puplished in the open source journal PLoS One:
Houska, T., Kraft, P., Chamorro-Chavez, A. and Breuer, L.: SPOTting Model Parameters Using a Ready-Made Python Package, PLoS ONE, 10(12), e0145180, doi:10.1371/journal.pone.0145180, 2015
The simplicity and flexibility enables the use and test of different algorithms without the need of complex codes:
sampler = spotpy.algorithms.sceua(model_setup()) # Initialize your model with a setup file sampler.sample(10000) # Run the model results = sampler.getdata() # Load the results spotpy.analyser.plot_parametertrace(results) # Show the results
Complex algorithms bring complex tasks to link them with a model. We want to make this task as easy as possible. Some features you can use with the SPOTPY package are:
Fitting models to evaluation data with different algorithms. Available algorithms are Monte Carlo (
MC), Markov-Chain Monte-Carlo (
MCMC), Maximum Likelihood Estimation (
MLE), Latin-Hypercube Sampling (
LHS), Simulated Annealing (
SA), Shuffled Complex Evolution Algorithm (
SCE-UA), Differential Evolution Adaptive Metropolis Algorithm (
DE-MCz), RObust Parameter Estimation (
ROPE), Artificial Bee Colony (
ABC), Dynamicallly Dimensioned Search algorithm (
DDS), Pareto Archived Dynamicallly Dimensioned Search algorithm (
PA-DDS) Fitness Scaled Chaotic Artificial Bee Colony (
FSCABC) and Fourier Amplitude Sensitivity Test (
Wide range of objective functions, likelihood functions and hydroligcal signatures to validate the sampled results. Available objective functions are: Bias, Nash-Sutcliff (
NSE), log Nash-Sutcliff (
logNSE), Logarithmic probability (
logp), Correlation Coefficient (
r), Coefficient of Determination (
r^2), Mean Squared Error (
MSE), Root Mean Squared Error (
RMSE), Mean Absolute Error (
MAE), Relative Root Mean Squared Error (
RRMSE), Agreement Index (
AI), Covariance, Decomposed MSE (
dMSE) and Kling-Gupta Efficiency (
Prebuild parameter distribution functions: Uniform, Normal, logNormal, Chisquare, Exponential, Gamma, Wald, Weilbull
Suited to perform uncertainty-, sensitivity analysis or calibration of a model.
MPI support for fast parallel computing
A progress bar monitoring the sampling loops. Enables you to plan your coffee breakes.
Use of Numpy functions as often as possible. This makes your coffe breakes short.
Different databases solutions:
ramstorage for fast sampling a simple and
sqltables the save solution for long duration samplings.
Automatic best run selecting and plotting
Parameter trace plotting
Parameter interaction plot including the Gaussian-kde function
Regression analysis between simulation and evaluation data
Posterior distribution plot
Convergence diagnostics with Gelman-Rubin and the Geweke plot
Relationship to other packages
A surprisingly small range of similar parameter estimation packages is available
- Pest Independent program for Model-Independent Parameter Estimation and Uncertainty Analysis
- OpenBugs Independent program for performing Bayesian inference Using Gibbs Sampling
- JAGS Independent program similar to OpenBUGS
- PyMC Comprehensive Python package to analyse models with MCMC techniques
- STAN Available in Python (amongst others) implementing MCMC techniques like NUTS, HMC and L-BFGS
- emcee Python package using a Affine Invariant Markov chain Monte Carlo Ensemble sampler
- BIP Python package for bayesian inference with a DREAM sampler
All of them have their pros and cons. To benchmark SPOTPY against these packages would be difficult because of wide variety of settings in different algorithms. The most related one is certainly PyMC, which brings many ideas into this framework. At the moment is PyMC limited to MCMC algorithms when analysing external deterministic models. To test other algorithms in such a straightforward way was the main reason why SPOTPY was developed. Consequently, none of the packages can offer such a wide range of different algorithms like SPOTPY.
The SPOTPY is an open-source package written in pure Python. It runs on all major platforms (Windows, Linux, Mac). SPOTPY requires just some standard packages:
Optional packages are:
all packages are pre-installed e.g. in the following packages:
pip install spotpy
The recommended place for the SPOTPY package is in the site-packages folder in your Python Path, just the location of all other Python packages.
SPOTPY can work with any parameter distributions. A standard setup uses pre-build distributions from NumPy.
To benchmark the model-runs with a value, SPOTPY comes along with a wide range of pre-build objective functions.
All algorithms realized in the SPOTPY package can work with the Distributions and objective functions. One can use them for
uncertainty-, sensitivity analysis or parameter optimization.
The three packages together can be run in any combination and results are stored in the
ram storage or in a
The results can be analysed with some pre-build statistics and plotting features.
Above: Overview about functionality of the SPOTPY package
__init__.py # Ensures that all needed files are loaded. analyser.py # Plotting features and statistic analysis. database.py # Ensures a secure data harbour during the sampling. objectivefunctions.py # Library of pre-build evaluation functions likelihoods.py # Library of pre-build evaluation functions signatures.py # Library of pre-build evaluation functions algorithms/ __init__.py # Ensures the availability of all algorithms demcz.py # Differential Evolution Markov Chain Monte Carlo lhs.py # Latin Hypercube Sampling mcmc.py # Metropolis Markov Chain Monte Carlo mle.py # Maximum Likelihood Estimation mc.py # Monte Carlo sceua.py # Shuffled Complex Evolution sa.py # Simulated annealing rope.py # RObust Parameter Estimation fast.py # Fourier Amplitude Sensitivity Testing abc.py # Artificial Bee Colony fscabc.py # Fitness Scaled Chaotic Artificial Bee Colony dream.py # Differential Evolution Adaptive Metropolis dds.py # Dynamically Dimensioned Search parallel/ mpi.py #Basic Parralel Computing features mpipool.py #Basic Parralel Computing features mproc.py #Basic Parralel Computing features sequential.py #Basic Parralel Computing features examples/ spotpy_setup_ackley.py # Example SPOTPY setup to analyse the Ackley function spotpy_setup_griewank.py # Example SPOTPY setup to analyse the Griewank function spotpy_setup_rosenbrock.py # Example SPOTPY setup to analyse the Rosenbrock function getting_started.py # Recommended test file for starters tutorials/ tutorial_rosenbrock.py # Source code for the Rosenbrock example the Tutorial tutorial_griewank.py # Source code for the Rosenbrock example the Tutorial tutorial_ackley.py # Source code for the Rosenbrock example the Tutorial tutorial_Parameterlist_iterator.py # Example how to sample given parameter combinations