Merge pull request #314 from farr/linear-dep-fix

Scale-invariant Test for Linear Dependence
dfm · Oct 17, 2019 · 9467f7a · 9467f7a
2 parents 1904ea5 + 45e72a6
commit 9467f7a
Showing 1 changed file with 3 additions and 8 deletions.
diff --git a/emcee/ensemble.py b/emcee/ensemble.py
@@ -244,14 +244,9 @@ def sample(
         state = State(initial_state, copy=True)
         if np.shape(state.coords) != (self.nwalkers, self.ndim):
             raise ValueError("incompatible input dimensions")
-        if (not skip_initial_state_check) and np.isclose(
-            np.linalg.det(
-                np.cov(state.coords, rowvar=False).reshape(
-                    (self.ndim, self.ndim)
-                )
-            ),
-            0,
-        ):
+        if (not skip_initial_state_check) and np.linalg.cond(
+             np.atleast_2d(np.cov(state.coords, rowvar=False))
+            ) > 1e8:
             warnings.warn(
                 "Initial state is not linearly independent and it will not "
                 "allow a full exploration of parameter space",