Use f-strings in pcigale rather than regular string as they are easier to read.

pcigale/__init__.py

@@ -39,8 +39,8 @@ def check(config):
     configuration = config.configuration
 
     if configuration:
-        print("With this configuration cigale will compute {} "
-              "models.".format(ParametersManager(configuration).size))
+        print(f"With this configuration cigale will compute "
+              f"{ParametersManager(configuration).size} models.")
 
 
 def run(config):
@@ -55,8 +55,8 @@ def run(config):
 
 def main():
     if sys.version_info[:2] < (3, 6):
-        raise Exception("Python {}.{} is unsupported. Please upgrade to "
-                        "Python 3.6 or later.".format(*sys.version_info[:2]))
+        raise Exception(f"Python {sys.version_info[0]}.{sys.version_info[1]} is"
+                        f" unsupported. Please upgrade to Python 3.6 or later.")
 
     # We set the sub processes start method to spawn because it solves
     # deadlocks when a library cannot handle being used on two sides of a

pcigale/analysis_modules/__init__.py

@@ -54,7 +54,7 @@ class AnalysisModule(object):
         if os.path.exists('out/'):
             name = datetime.now().strftime("%Y-%m-%d_%H:%M:%S") + '_out/'
             os.rename('out/', name)
-            print("The out/ directory was renamed to {}".format(name))
+            print(f"The out/ directory was renamed to {name}")
 
         os.mkdir('out/')
         shutil.copy('pcigale.ini', 'out/')

pcigale/analysis_modules/pdf_analysis/__init__.py

@@ -137,7 +137,7 @@ class PdfAnalysis(AnalysisModule):
         results = []
         nblocks = len(params.blocks)
         for iblock in range(nblocks):
-            print('\nProcessing block {}/{}...'.format(iblock + 1, nblocks))
+            print(f"\nProcessing block {iblock + 1}/{nblocks}...")
             # We keep the models if there is only one block. This allows to
             # avoid recomputing the models when we do a mock analysis
             if not hasattr(self, '_models'):
@@ -205,7 +205,7 @@ class PdfAnalysis(AnalysisModule):
 
             # For the mock analysis we do not save the ancillary files.
             for k in ['best_sed', 'chi2']:
-                conf['analysis_params']["save_{}".format(k)] = False
+                conf['analysis_params'][f"save_{k}"] = False
 
             # We replace the observations with a mock catalogue..
             obs.generate_mock(results)

pcigale/analysis_modules/pdf_analysis/utils.py

@@ -21,8 +21,8 @@ def save_chi2(obs, variable, models, chi2, values):
     """Save the chi² and the associated physocal properties
 
     """
-    fname = 'out/{}_{}_chi2-block-{}.npy'.format(obs.id, variable.replace('/',
-                                                 '_'), models.iblock)
+    fname = f"out/{obs.id}_{variable.replace('/', '_')}_chi2-block-" \
+            f"{models.iblock}.npy"
     data = np.memmap(fname, dtype=np.float64, mode='w+',
                      shape=(2, chi2.size))
     data[0, :] = chi2

pcigale/analysis_modules/pdf_analysis/workers.py

@@ -209,9 +209,9 @@ def analysis(idx, obs):
                                        gbl_models.block.start)
     else:
         # It sometimes happens because models are older than the Universe's age
-        print("No suitable model found for the object {}. It may be that "
-              "models are older than the Universe or that your chi² are very "
-              "large.".format(obs.id))
+        print(f"No suitable model found for the object {obs.id}. It may be that"
+              f" models are older than the Universe or that your chi² are very "
+              f"large.")
 
     gbl_counter.inc()
 
@@ -269,6 +269,6 @@ def bestfit(oidx, obs):
                                                    * corr_dz
 
     if gbl_conf['analysis_params']["save_best_sed"]:
-        sed.to_fits('out/{}'.format(obs.id), scaling * corr_dz)
+        sed.to_fits(f"out/{obs.id}", scaling * corr_dz)
 
     gbl_counter.inc()

pcigale/analysis_modules/savefluxes/__init__.py

@@ -71,8 +71,7 @@ class SaveFluxes(AnalysisModule):
     def _compute_models(self, conf, obs, params):
         nblocks = len(params.blocks)
         for iblock in range(nblocks):
-            print('Computing models for block {}/{}...'.format(iblock + 1,
-                                                               nblocks))
+            print(f"Computing models for block {iblock + 1}/{nblocks}...")
 
             models = ModelsManager(conf, obs, params, iblock)
             counter = Counter(len(params.blocks[iblock]), 50, 250)
@@ -86,7 +85,7 @@ class SaveFluxes(AnalysisModule):
                 counter.pprint(len(params.blocks[iblock]))
 
             print("Saving the models ....")
-            models.save('models-block-{}'.format(iblock))
+            models.save(f"models-block-{iblock}")
 
 
     def process(self, conf):

pcigale/analysis_modules/savefluxes/workers.py

@@ -67,6 +67,6 @@ def fluxes(idx, midx):
             gbl_models.intprop[prop][idx] = sed.info[prop]
 
     if gbl_save is True:
-        sed.to_fits("out/{}".format(midx))
+        sed.to_fits(f"out/{midx}")
 
     gbl_counter.inc()

pcigale/analysis_modules/utils.py

@@ -66,6 +66,5 @@ class Counter:
 
     def pprint(self, n):
         dt = time.time() - self.t0
-        print("{}/{} performed in {:.1f} seconds ({:.1f}/s)".
-              format(n, self.nmodels, dt, n / dt),
+        print(f"{n}/{self.nmodels} performed in {dt:.1f} seconds ({n/dt:.1f}/s)",
               end="\n" if n == self.nmodels else "\r")

pcigale/data/__init__.py

@@ -367,8 +367,8 @@ class Database(object):
                          result.spec_table)
         else:
             raise DatabaseLookupError(
-                "The M2005 SSP for imf <{0}> and metallicity <{1}> is not in "
-                "the database.".format(imf, metallicity))
+                f"The M2005 SSP for imf <{imf}> and metallicity <{metallicity}>"
+                f" is not in the database.")
 
     def get_m2005_parameters(self):
         """Get parameters for the Maraston 2005 stellar models.
@@ -431,8 +431,8 @@ class Database(object):
                         result.spec_table)
         else:
             raise DatabaseLookupError(
-                "The BC03 SSP for imf <{0}> and metallicity <{1}> is not in "
-                "the database.".format(imf, metallicity))
+                f"The BC03 SSP for imf <{imf}> and metallicity <{metallicity}> "
+                f"is not in the database.")
 
     def get_bc03_parameters(self):
         """Get parameters for the Bruzual & Charlot 2003 stellar models.
@@ -499,8 +499,8 @@ class Database(object):
                           result.lumin)
         else:
             raise DatabaseLookupError(
-                "The DL2007 model for qpah <{0}>, umin <{1}>, and umax <{2}> "
-                "is not in the database.".format(qpah, umin, umax))
+                f"The DL2007 model for qpah <{qpah}>, umin <{umin}>, and umax "
+                f"<{umax}> is not in the database.")
 
     def get_dl2007_parameters(self):
         """Get parameters for the DL2007 models.
@@ -570,9 +570,8 @@ class Database(object):
                           result.wave, result.lumin)
         else:
             raise DatabaseLookupError(
-                "The DL2014 model for qpah <{0}>, umin <{1}>, umax <{2}>, and "
-                "alpha <{3}> is not in the database."
-                .format(qpah, umin, umax, alpha))
+                f"The DL2014 model for qpah <{qpah}>, umin <{umin}>, umax "
+                f"<{umax}>, and alpha <{alpha}> is not in the database.")
 
     def get_dl2014_parameters(self):
         """Get parameters for the DL2014 models.
@@ -638,8 +637,8 @@ class Database(object):
                             result.lumin)
         else:
             raise DatabaseLookupError(
-                "The Dale2014 template for frac_agn <{0}> and alpha <{1}> "
-                "is not in the database.".format(frac_agn, alpha))
+                f"The Dale2014 template for frac_agn <{frac_agn}> and alpha "
+                f"<{alpha}> is not in the database.")
 
     def get_dale2014_parameters(self):
         """Get parameters for the Dale 2014 models.
@@ -884,8 +883,8 @@ class Database(object):
                                  result.lumin)
         else:
             raise DatabaseLookupError(
-                "The Schreiber2016 template for type <{0}> and tdust <{1}> "
-                "is not in the database.".format(type, tdust))
+                f"The Schreiber2016 template for type <{type}> and tdust "
+                f"<{tdust}> is not in the database.")
 
     def get_schreiber2016_parameters(self):
         """Get parameters for the Scnreiber 2016 models.
@@ -956,9 +955,8 @@ class Database(object):
                           result.wave, result.lumin)
         else:
             raise DatabaseLookupError(
-                "The THEMIS model for qhac <{0}>, umin <{1}>, umax <{2}>, and "
-                "alpha <{3}> is not in the database."
-                .format(qhac, umin, umax, alpha))
+                f"The THEMIS model for qhac <{qhac}>, umin <{umin}>, umax "
+                f"<{umax}>, and alpha <{alpha}> is not in the database.")
 
     def _get_parameters(self, schema):
         """Generic function to get parameters from an arbitrary schema.
@@ -1038,7 +1036,7 @@ class Database(object):
                     raise Exception('The database is not writable.')
         else:
             raise DatabaseLookupError(
-                "The filter <{0}> is not in the database".format(name))
+                f"The filter <{name}> is not in the database")
 
     def get_filter(self, name):
         """
@@ -1067,7 +1065,7 @@ class Database(object):
                           result.pivot_wavelength)
         else:
             raise DatabaseLookupError(
-                "The filter <{0}> is not in the database".format(name))
+                f"The filter <{name}> is not in the database")
 
     def get_filter_names(self):
         """Get the list of the name of the filters in the database.

pcigale/managers/models.py

@@ -66,6 +66,6 @@ class ModelsManager(object):
         for prop in sorted(self.intprop.keys()):
             table.add_column(Column(self.intprop[prop], name=prop))
 
-        table.write("out/{}.fits".format(filename))
-        table.write("out/{}.txt".format(filename), format='ascii.fixed_width',
+        table.write(f"out/{filename}.fits")
+        table.write(f"out/{filename}.txt", format='ascii.fixed_width',
                     delimiter=None)

pcigale/managers/observations.py

@@ -103,15 +103,15 @@ class ObservationsManagerPassbands(object):
         """
         for item in self.tofit + self.tofit_err:
             if item not in self.table.colnames:
-                raise Exception("{} to be taken in the fit but not present "
-                                "in the observation table.".format(item))
+                raise Exception(f"{item} to be taken in the fit but not present"
+                                f" in the observation table.")
 
         for item in self.table.colnames:
             if (item != 'id' and item != 'redshift' and item != 'distance' and
                     item not in self.tofit + self.tofit_err):
                 self.table.remove_column(item)
-                print("Warning: {} in the input file but not to be taken into"
-                      " account in the fit.".format(item))
+                print(f"Warning: {item} in the input file but not to be taken "
+                      f"into account in the fit.")
 
     def _check_errors(self, defaulterror=0.1):
         """Check whether the error columns are present. If not, add them.
@@ -148,9 +148,8 @@ class ObservationsManagerPassbands(object):
                                 name=error)
                 self.table.add_column(colerr,
                                       index=self.table.colnames.index(item)+1)
-                print("Warning: {}% of {} taken as errors.".format(defaulterror *
-                                                                   100.,
-                                                                   item))
+                print(f"Warning: {defaulterror * 100}% of {item} taken as "
+                      f"errors.")
 
     def _check_invalid(self, upperlimits=False, threshold=-9990.):
         """Check whether invalid data are correctly marked as such.
@@ -194,8 +193,7 @@ class ObservationsManagerPassbands(object):
                 self.extprops.remove(item)
                 self.extprops_err.remove(item + '_err')
             self.table.remove_columns([item, item + '_err'])
-            print("Warning: {} removed as no valid data was found.".format(
-                allinvalid))
+            print(f"Warning: {allinvalid} removed as no valid data was found.")
 
     def _add_model_error(self, modelerror=0.1):
         """Add in quadrature the error of the model to the input error.
@@ -256,9 +254,9 @@ class ObservationsManagerPassbands(object):
             Root of the filename where to save the observations.
 
         """
-        self.table.write('out/{}.fits'.format(filename))
-        self.table.write('out/{}.txt'.format(filename),
-                         format='ascii.fixed_width', delimiter=None)
+        self.table.write(f'out/{filename}.fits')
+        self.table.write(f'out/{filename}.txt', format='ascii.fixed_width',
+                         delimiter=None)
 
 
 class ObservationsManagerVirtual(object):

pcigale/managers/results.py

@@ -313,9 +313,10 @@ class BestResultsManager(object):
         chi2_red = self.chi2 / (nobs - 1)
         # If low values of reduced chi^2, it means that the data are overfitted
         # Errors might be under-estimated or not enough valid data.
-        print("\n{}% of the objects have chi^2_red~0 and {}% chi^2_red<0.5"
-              .format(np.round((chi2_red < 1e-12).sum() / chi2_red.size, 1),
-                      np.round((chi2_red < 0.5).sum() / chi2_red.size, 1)))
+        print(f"\n{np.round((chi2_red < 1e-12).sum() / chi2_red.size, 1)}% of "
+              f"the objects have chi^2_red~0 and "
+              f"{np.round((chi2_red < 0.5).sum() / chi2_red.size, 1)}% "
+              f"chi^2_red<0.5")
 
 
 class ResultsManager(object):
@@ -405,6 +406,6 @@ class ResultsManager(object):
                                     name="best."+band, unit=unit))
 
 
-        table.write("out/{}.txt".format(filename), format='ascii.fixed_width',
+        table.write(f"out/{filename}.txt", format='ascii.fixed_width',
                     delimiter=None)
-        table.write("out/{}.fits".format(filename), format='fits')
+        table.write(f"out/{filename}.fits", format='fits')

pcigale/sed/io/fits.py

@@ -37,10 +37,10 @@ def save_sed_to_fits(sed, prefix, norm=1.):
     for name in sed.contribution_names:
         table[name] = Column(norm * sed.get_lumin_contribution(name),
                              unit="W/nm")
-    table.write("{}_best_model.fits".format(prefix))
+    table.write(f"{prefix}_best_model.fits")
 
     if sed.sfh is not None:
         table = Table(meta=info)
         table["time"] = Column(np.arange(sed.sfh.size), unit="Myr")
         table["SFR"] = Column(norm * sed.sfh, unit="Msun/yr")
-        table.write("{}_SFH.fits".format(prefix))
+        table.write(f"{prefix}_SFH.fits")

pcigale/sed_modules/bc03.py

@@ -63,7 +63,7 @@ class BC03(SedModule):
             elif self.imf == 1:
                 self.ssp = database.get_bc03('chab', self.metallicity)
             else:
-                raise Exception("IMF #{} unknown".format(self.imf))
+                raise Exception(f"IMF #{self.imf} unknown")
 
     def process(self, sed):
         """Add the convolution of a Bruzual and Charlot SSP to the SED

pcigale/sed_modules/fluxes.py

@@ -56,7 +56,7 @@ class Fluxes(SedModule):
 
         for filter_ in filter_list:
             sed.add_info(
-                "param.{}".format(filter_),
+                f"param.{filter_}",
                 sed.compute_fnu(filter_),
                 True
             )

pcigale/sed_modules/m2005.py

@@ -61,7 +61,7 @@ class M2005(SedModule):
             with Database() as database:
                 self.ssp = database.get_m2005('krou', self.metallicity)
         else:
-            raise Exception("IMF #{} unknown".format(self.imf))
+            raise Exception(f"IMF #{self.imf} unknown")
 
     def process(self, sed):
         """Add the convolution of a Maraston 2005 SSP to the SED

pcigale/sed_modules/redshifting.py

@@ -160,8 +160,8 @@ class Redshifting(SedModule):
         # Raise an error when applying a negative redshift. This module is
         # not for blue-shifting.
         if self.redshift < 0.:
-            raise Exception("The redshift provided is negative <{}>."
-                            .format(self.redshift))
+            raise Exception(f"The redshift provided is negative "
+                            f"({self.redshift}).")
 
         self.universe_age = cosmology.age(self.redshift).value * 1000.
         if self.redshift == 0.:
@@ -188,8 +188,8 @@ class Redshifting(SedModule):
         # If the SED is already redshifted, raise an error.
         if ('universe.redshift' in sed.info and
             sed.info['universe.redshift'] > 0.):
-            raise Exception("The SED is already redshifted <z={}>."
-                            .format(sed.info['universe.redshift']))
+            raise Exception(f"The SED is already redshifted (z="
+                            f"{sed.info['universe.redshift']}).")
 
         if redshift > 0.:
             # We redshift directly the SED wavelength grid

pcigale/sed_modules/restframe_parameters.py

@@ -220,14 +220,14 @@ class RestframeParam(SedModule):
 
         if 'nebular.lines_young' in sed.contribution_names:
             for line, EW in self.EW(sed).items():
-                sed.add_info("param.EW({}/{})".format(*line), EW)
+                sed.add_info(f"param.EW({line[0]}/{line[1]})", EW)
 
         for filt in self.lumin_filters:
-            sed.add_info("param.restframe_Lnu({})".format(filt),
+            sed.add_info(f"param.restframe_Lnu({filt}),
                          fluxes[filt] * self.to_lumin,
                          True)
         for filt1, filt2 in self.colours:
-            sed.add_info("param.restframe_{}-{}".format(filt1, filt2),
+            sed.add_info(f"param.restframe_{filt1}-{filt2}",
                          2.5 * np.log10(fluxes[filt2]/fluxes[filt1]))
 
 

pcigale/sed_modules/sfhperiodic.py

@@ -90,7 +90,7 @@ class SfhPeriodic(SedModule):
             burst = np.zeros_like(time_grid)
             burst[:int(self.tau_bursts)+1] = 1.
         else:
-            raise Exception("Burst type {} unknown.".format(self.type_bursts))
+            raise Exception(f"Burst type {self.type_bursts} unknown.")
 
         for t_burst in np.arange(0, age, self.delta_bursts):
             self.sfr += burst

pcigale/session/configuration.py

@@ -139,8 +139,8 @@ class Configuration(object):
 
         self.config['cores'] = ""
         self.config.comments['cores'] = [""] + wrap(
-            "Number of CPU cores available. This computer has {} cores."
-            .format(mp.cpu_count()))
+            f"Number of CPU cores available. This computer has "
+            f"{mp.cpu_count()} cores.")
         self.spec['cores'] = "integer(min=1)"
 
         self.config.write()
@@ -187,9 +187,8 @@ class Configuration(object):
             # band
             for band in bands:
                 if band.endswith('_err') and (band[:-4] not in bands):
-                    raise Exception("The observation table as a {} column "
-                                    "but no {} column.".format(band,
-                                                               band[:-4]))
+                    raise Exception(f"The observation table as a {band} column "
+                                    f"but no {band[:-4]} column.")
 
             self.config['bands'] = bands
         else:
@@ -276,10 +275,10 @@ class Configuration(object):
             for module, param, message in configobj.flatten_errors(self.config,
                                                                    validity):
                 if len(module) > 0:
-                    print("Module {}, parameter {}: {}".format('/'.join(module),
-                                                               param, message))
+                    print(f"Module {'/'.join(module)}, parameter {param}: "
+                          f"{message}")
                 else:
-                    print("Parameter {}: {}".format(param, message))
+                    print(f"Parameter {param}: {message}")
             print("Run the same command after having fixed pcigale.ini.")
 
             return None
@@ -327,8 +326,8 @@ class Configuration(object):
         for module in modules:
             if all([user_module not in modules[module] for user_module in
                     self.config['sed_modules']]):
-                print("{} Options are: {}.".
-                      format(comments[module], ', '.join(modules[module])))
+                print(f"{comments[module]} Options are: "
+                      f"{', '.join(modules[module])}.")
 
     def complete_redshifts(self):
         """Complete the configuration when the redshifts are missing from the