autofit.SamplesStored#
- class autofit.SamplesStored(model: AbstractPriorModel, sample_list: List[Sample], samples_info: Optional[Dict] = None)[source]#
Bases:
SamplesPDF
The Samples of a non-linear search, specifically the samples of a NonLinearSearch which maps out the posterior of parameter space and thus does provide information on parameter errors.
- Parameters:
model (af.ModelMapper) – Maps input vectors of unit parameter values to physical values and model instances via priors.
Methods
draw_randomly_via_pdf
The parameter vector of an individual sample of the non-linear search drawn randomly from the PDF, returned as a 1D list.
error_magnitudes_at_sigma
The magnitude of every error after marginalization in 1D at an input sigma value of the probability density function (PDF), returned as two lists of values corresponding to the lower and upper errors.
errors_at_lower_sigma
The lower error of every parameter marginalized in 1D at an input sigma value of its probability density function (PDF), returned as a list.
errors_at_sigma
The lower and upper error of every parameter marginalized in 1D at an input sigma value of its probability density function (PDF), returned as a list.
errors_at_upper_sigma
The upper error of every parameter marginalized in 1D at an input sigma value of its probability density function (PDF), returned as a list.
from_list_info_and_model
from_sample_index
The parameters of an individual sample of the non-linear search, returned as a model instance.
from_table
Write a table of parameters, posteriors, priors and likelihoods
info_to_json
max_log_likelihood
The parameters of the maximum log likelihood sample of the NonLinearSearch returned as a model instance or list of values.
max_log_posterior
The parameters of the maximum log posterior sample of the NonLinearSearch returned as a model instance.
median_pdf
The median of the probability density function (PDF) of every parameter marginalized in 1D, returned as a model instance or list of values.
minimise
A copy of this object with only important samples retained
model_absolute
Returns a model where every free parameter is a GaussianPrior with mean the previous result's inferred maximum log likelihood parameter values and sigma the input absolute value a.
model_bounded
Returns a model where every free parameter is a UniformPrior with lower_limit and upper_limit the previous result's inferred maximum log likelihood parameter values minus and plus the bound `b.
model_relative
Returns a model where every free parameter is a GaussianPrior with mean the previous result's inferred maximum log likelihood parameter values and sigma a relative value from the result r.
offset_values_via_input_values
The values of an input_vector offset by the median_pdf(as_instance=False) (the PDF medians).
path_map_for_model
samples_above_weight_threshold_from
Returns a new Samples object containing only the samples with a weight above the input threshold.
save_covariance_matrix
Save the covariance matrix as a CSV file.
subsamples
summary
values_at_lower_sigma
The lower value of every parameter marginalized in 1D at an input sigma value of its probability density function (PDF), returned as a list.
values_at_sigma
The value of every parameter marginalized in 1D at an input sigma value of its probability density function (PDF), returned as two lists of values corresponding to the lower and upper values parameter values.
values_at_upper_sigma
The upper value of every parameter marginalized in 1D at an input sigma value of its probability density function (PDF), returned as a list.
values_for_path
Returns the value for a variable with a given path for each sample in the model
with_paths
Create a copy of this object with only attributes specified by a list of paths.
without_paths
Create a copy of this object with only attributes not specified by a list of paths.
write_table
Write a table of parameters, posteriors, priors and likelihoods.
Attributes
covariance_matrix
Compute the covariance matrix of the non-linear search samples, using the method np.cov() which is described at the following link:
instance
instances
One model instance for each sample
log_evidence
log_likelihood
log_likelihood_list
log_posterior_list
log_prior_list
max_log_likelihood_index
The index of the sample with the highest log likelihood.
max_log_likelihood_sample
The index of the sample with the highest log likelihood.
max_log_posterior_index
The index of the sample with the highest log posterior.
max_log_posterior_sample
names
A list of names of unique priors in the same order as prior ids (and therefore sample columns)
parameter_lists
parameters_extract
paths
A list of paths to unique priors in the same order as prior ids (and therefore sample columns)
pdf_converged
To analyse and visualize samples the analysis must be sufficiently converged to produce smooth enough PDF for error estimate and PDF generation.
prior_means
The mean of every parameter used to link its inferred values and errors to priors used to sample the same (or similar) parameters in a subsequent search, where:
time
total_iterations
total_samples
unconverged_sample_size
If a set of samples are unconverged, alternative methods to compute their means, errors, etc are used.
weight_list