Merge branch...

Merge branch '586-bilby-gw-conversion-module-for-waveforms-which-use-a-custom-reference-frequency' into 'master'

Resolve "`bilby.gw.conversion` module for waveforms which use a custom reference frequency"

Closes #586

See merge request !1080

bilby/gw/__init__.py

 from . import (conversion, cosmology, detector, eos, likelihood, prior,
                result, source, utils, waveform_generator)
-from .waveform_generator import WaveformGenerator
+from .waveform_generator import WaveformGenerator, LALCBCWaveformGenerator
 from .likelihood import GravitationalWaveTransient
 from .detector import calibration
 

bilby/gw/waveform_generator.py

@@ -4,6 +4,7 @@ from ..core import utils
 from ..core.series import CoupledTimeAndFrequencySeries
 from ..core.utils import PropertyAccessor
 from .conversion import convert_to_lal_binary_black_hole_parameters
+from .utils import lalsim_GetApproximantFromString
 
 
 class WaveformGenerator(object):
@@ -253,3 +254,18 @@ class WaveformGenerator(object):
             raise AttributeError('Either time or frequency domain source '
                                  'model must be provided.')
         return set(utils.infer_parameters_from_function(model))
+
+
+class LALCBCWaveformGenerator(WaveformGenerator):
+    """ A waveform generator with specific checks for LAL CBC waveforms """
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+        self.validate_reference_frequency()
+
+    def validate_reference_frequency(self):
+        from lalsimulation import SimInspiralGetSpinFreqFromApproximant, LAL_SIM_INSPIRAL_SPINS_FLOW
+        waveform_approximant = self.waveform_arguments["waveform_approximant"]
+        waveform_approximant_number = lalsim_GetApproximantFromString(waveform_approximant)
+        if SimInspiralGetSpinFreqFromApproximant(waveform_approximant_number) == LAL_SIM_INSPIRAL_SPINS_FLOW:
+            if self.waveform_arguments["reference_frequency"] != self.waveform_arguments["minimum_frequency"]:
+                raise ValueError(f"For {waveform_approximant}, reference_frequency must equal minimum_frequency")