Add a delayed SFH modules made by Véronique.

pcigale/creation_modules/sfhdelayed.py

+# Copyright (C) 2013 Centre de données Astrophysiques de Marseille
+# Copyright (C) 2014 Laboratoire d'Astrophysique de Marseille
+# Copyright (C) 2014 University of Cambridge
+# Licensed under the CeCILL-v2 licence - see Licence_CeCILL_V2-en.txt
+# Author: Yannick Roehlly, Véronique Buat & Médéric Boquien
+
+"""
+Delayed tau model for star formation history
+============================================
+
+This module implements a star formation history (SFH) described as a delayed
+rise of the SFR up to a maximum, followed by an exponential decrease.
+
+"""
+
+import numpy as np
+from collections import OrderedDict
+from . import CreationModule
+
+# Time lapse used in the age grid in Myr. If should be consistent with the
+# time lapse in the SSP modules.
+AGE_LAPSE = 1
+
+
+class SFHDelayed(CreationModule):
+    """Delayed tau model for Star Formation History
+
+    This module sets the SED star formation history (SFH) proportional to time,
+    with a declining exponential parametrised with a time-scale (tau_main).
+
+    """
+
+    parameter_list = OrderedDict([
+        ("tau_main", (
+            "float",
+            "e-folding time of the main stellar population model in Myr.",
+            None
+        )),
+        ("age", (
+            "integer",
+            "Age of the oldest stars in the galaxy in Myr. The precision "
+            "is 1 Myr.",
+            None
+        ))
+    ])
+
+    out_parameter_list = OrderedDict([
+        ("tau_main", "e-folding time of the main stellar population model "
+                     "in Myr."),
+        ("age", "Age of the oldest stars in the galaxy in Myr.")
+    ])
+
+    def process(self, sed):
+        """
+        Parameters
+        ----------
+        sed : pcigale.sed.SED object
+
+        """
+        tau_main = float(self.parameters["tau_main"])
+        age = int(self.parameters["age"])
+
+        # Time grid and age. If needed, the age is rounded to the inferior Myr
+        time_grid = np.arange(AGE_LAPSE, age + AGE_LAPSE, AGE_LAPSE)
+
+        # Main SFR
+        sfr = time_grid / tau_main**2 * np.exp(-time_grid / tau_main)
+
+        # We normalise the SFH to have one solar mass produced.
+        sfr = sfr / np.trapz(sfr * 1.e6, time_grid)
+
+        sed.add_module(self.name, self.parameters)
+
+        # Add the sfh and the output parameters to the SED.
+        sed.sfh = (time_grid, sfr)
+        sed.add_info("sfh.tau_main", tau_main)
+
+# CreationModule to be returned by get_module
+Module = SFHDelayed

pcigale/session/configuration.py

@@ -125,7 +125,7 @@ class Configuration(object):
         self.config['creation_modules'] = []
         self.config.comments['creation_modules'] = [""] + wrap(
             "Order of the modules use for SED creation. Available modules:"
-            "SFH: sfh2exp, sfhfromfile ; "
+            "SFH: sfh2exp, sfhdelayed, sfhfromfile ; "
             "SSP: bc03, m2005 ; "
             "Nebular: nebular ; "
             "Attenuation: dustatt_calzleit, dustatt_powerlaw ; "