Merge 595b487 into 9a9cdd0

sncosmo/fitting.py

@@ -5,6 +5,7 @@
 import time
 import warnings
 from collections import OrderedDict
+from packaging.version import parse as version_parse
 
 import numpy as np
 
@@ -50,15 +51,6 @@ def generate_chisq(data, model, spectra, signature='iminuit', modelcov=False):
     # parameters)
     if signature == 'iminuit':
         def chisq(*parameters):
-            # When a fit fails, iminuit sometimes calls the chisq function with
-            # the parameters set to nan. This sometimes leads to a segfault in
-            # sncosmo because the internal functions (specifically
-            # BicubicInterpolator) aren't designed to handle that. See
-            # https://github.com/sncosmo/sncosmo/issues/266 for details. For
-            # now, return nan to minuit if it tries to set any parameter to
-            # nan.
-            if np.any(np.isnan(parameters)):
-                return np.nan
             model.parameters = parameters
 
             full_chisq = 0.
@@ -662,6 +654,11 @@ def fit_lc(data=None, model=None, vparam_names=[], bounds=None, spectra=None,
             _print_iminuit_params(vparam_names, kwargs)
             print()
 
+        # Set up keyword arguments to Migrad.minuit
+        migrad_kwargs = {"ncall": maxcall}
+        if version_parse(iminuit.__version__) >= version_parse("1.5.2"):
+            migrad_kwargs["iterate"] = 1
+
         # run once with no model covariance, regardless of whether
         # modelcov=True
         fitchisq = generate_chisq(fitdata, model, spectra, signature='iminuit',
@@ -680,7 +677,7 @@ def fit_lc(data=None, model=None, vparam_names=[], bounds=None, spectra=None,
                            forced_parameters=model.param_names,
                            print_level=(1 if verbose >= 2 else 0),
                            throw_nan=True, **kwargs)
-        d, l = m.migrad(ncall=maxcall)
+        d, l = m.migrad(**migrad_kwargs)
         if verbose:
             print("{} function calls; {} dof.".format(d.nfcn, ndof))
 
@@ -737,7 +734,7 @@ def fit_lc(data=None, model=None, vparam_names=[], bounds=None, spectra=None,
                                forced_parameters=model.param_names,
                                print_level=(1 if verbose >= 2 else 0),
                                throw_nan=True, **kwargs)
-            d, l = m.migrad(ncall=maxcall)
+            d, l = m.migrad(**migrad_kwargs)
 
             if verbose:
                 print("{} function calls; {} dof.".format(d.nfcn, ndof))

sncosmo/salt2utils.pyx

@@ -215,7 +215,7 @@ cdef class BicubicInterpolator(object):
             y_j = yc[j]
 
             # if y is out of range, we won't be using the value at all
-            if (y_j < self.ymin or y_j > self.ymax):
+            if (not (y_j >= self.ymin and y_j <= self.ymax)):
                 yflagvec[j] = -1
             else:
                 iy = find_index_unsafe(self.yval, self.ny, y_j, iy)
@@ -243,7 +243,7 @@ cdef class BicubicInterpolator(object):
             x_i = xc[i]
 
             # precompute some stuff for x
-            if (x_i < self.xmin or x_i > self.xmax):
+            if (not (x_i >= self.xmin and x_i <= self.xmax)):
                 xflag = -1
             else:
                 ix = find_index_unsafe(self.xval, self.nx, x_i, ix)