Add direct call

vega/samplers/pocomc.py

@@ -1,3 +1,5 @@
+import os.path
+import sys
 from pathlib import Path
 
 import numpy as np
@@ -8,14 +10,97 @@
 from multiprocessing import Pool
 from scipy.stats import uniform
 
-from vega.samplers.sampler_interface import Sampler
+from vega import VegaInterface
+# from vega.samplers.sampler_interface import Sampler
+from vega.parameters.param_utils import build_names
 
 
-class PocoMC(Sampler):
+class PocoMC:
     """ Interface between Vega and the PocoMC sampler """
 
     def __init__(self, args):
-        super().__init__(args)
+        # super().__init__(args)
+        """
+
+        Parameters
+        ----------
+        polychord_setup : ConfigParser
+            Polychord section from the main config
+        limits : dict
+            Dictionary with the prior limits of the sampled parameters
+        log_lik_func : f(params)
+            Log Likelihood function to be passed to Polychord
+        """
+        self.mpi_comm = MPI.COMM_WORLD
+        self.cpu_rank = self.mpi_comm.Get_rank()
+
+        self.print_func('Initializing Vega')
+
+        # Initialize Vega and get the sampling parameters
+        self.vega = VegaInterface(args.config)
+        sampling_params = self.vega.sample_params['limits']
+
+        self.print_func('Finished initializing Vega')
+
+        # Check if we need to run over a Monte Carlo mock
+        run_montecarlo = self.vega.main_config['control'].getboolean('run_montecarlo', False)
+        if run_montecarlo and self.vega.mc_config is not None:
+            # Get the MC seed and forecast flag
+            seed = self.vega.main_config['control'].getint('mc_seed', 0)
+            forecast = self.vega.main_config['control'].getboolean('forecast', False)
+
+            # Create the mocks
+            self.vega.monte_carlo_sim(self.vega.mc_config['params'], seed=seed, forecast=forecast)
+
+            # Set to sample the MC params
+            sampling_params = self.vega.mc_config['sample']['limits']
+            self.print_func('Created Monte Carlo realization of the correlation')
+        elif run_montecarlo:
+            raise ValueError('You asked to run over a Monte Carlo simulation,'
+                             ' but no "[monte carlo]" section provided.')
+
+        # Run sampler
+        if not self.vega.run_sampler:
+            raise ValueError(
+                'Warning: You called "run_vega_mpi.py" without asking'
+                ' for the sampler. Add "run_sampler = True" to the "[control]" section.'
+            )
+
+        self.limits = sampling_params
+        self.names = list(sampling_params.keys())
+        self.num_params = len(sampling_params)
+        self.num_derived = 0
+        # self.log_lik = log_lik_func
+
+        if self.vega.sampler == 'Polychord':
+            sampler_config = self.vega.main_config['Polychord']
+        elif self.vega.sampler == 'PocoMC':
+            sampler_config = self.vega.main_config['PocoMC']
+
+        self.getdist_latex = sampler_config.getboolean('getdist_latex', True)
+
+        # Check limits are well defined
+        for lims in self.limits.values():
+            if None in lims:
+                raise ValueError('Sampler needs well defined prior limits.'
+                                 ' You passed a None. Please give numbers, or'
+                                 ' just say par_name = True to use defaults.')
+
+        # Check the path and get the paramnames path
+        self.path = os.path.expandvars(sampler_config.get('path'))
+        self.name = sampler_config.get('name')
+
+        output_path = Path(self.path)
+        err_msg = ("The sampler 'path' does not correspond to an existing"
+                   " folder. Create the output folder before running.")
+        assert output_path.exists(), err_msg
+        parnames_path = output_path / (self.name + '.paramnames')
+
+        # Write parameter names
+        self.write_parnames(parnames_path)
+
+        # Initialize the sampler settings
+        self.get_sampler_settings(sampler_config, self.num_params, self.num_derived)
 
     def get_sampler_settings(self, sampler_config, num_params, num_derived):
         # Initialize the pocomc settings
@@ -85,3 +170,28 @@ def write_chain(self):
         # Print Evidence
         logZ, logZerr = self.pocomc_sampler.evidence()
         print(f'log(Z) = {logZ} +/- {logZerr}')
+
+    def print_func(self, message):
+        if self.cpu_rank == 0:
+            print(message)
+        sys.stdout.flush()
+
+    def write_parnames(self, parnames_path):
+        mpi_comm = MPI.COMM_WORLD
+        cpu_rank = mpi_comm.Get_rank()
+
+        if cpu_rank == 0:
+            print('Writing parameter names')
+            sys.stdout.flush()
+            latex_names = build_names(list(self.names))
+            with open(parnames_path, 'w') as f:
+                for name, latex in latex_names.items():
+                    if self.getdist_latex:
+                        f.write('%s    %s\n' % (name, latex))
+                    else:
+                        f.write('%s    $%s$\n' % (name, latex))
+            print('Finished writing parameter names')
+            sys.stdout.flush()
+
+        mpi_comm.barrier()
+