Merge pull request #2319 from obspy/backport-2280

Backport 2280

obspy/taup/tau_branch.py

@@ -8,6 +8,8 @@
 from future.builtins import *  # NOQA
 from future.utils import native_str
 
+import warnings
+
 import numpy as np
 
 from .c_wrappers import clibtau
@@ -153,15 +155,16 @@ def insert(self, ray_param, s_mod, index):
     def shift_branch(self, index):
         new_size = len(self.dist) + 1
 
-        self.time.resize(new_size)
+        self.time = self._robust_resize(self.time, new_size)
+
         self.time[index + 1:] = self.time[index:-1]
         self.time[index] = 0
 
-        self.dist.resize(new_size)
+        self.dist = self._robust_resize(self.dist, new_size)
         self.dist[index + 1:] = self.dist[index:-1]
         self.dist[index] = 0
 
-        self.tau.resize(new_size)
+        self.tau = self._robust_resize(self.tau, new_size)
         self.tau[index + 1:] = self.tau[index:-1]
         self.tau[index] = 0
 
@@ -477,3 +480,19 @@ def _from_array(arr):
                 arr_ = arr_[()]
             setattr(branch, key, arr_)
         return branch
+
+    @staticmethod
+    def _robust_resize(arr, new_size):
+        """
+        Try to resize an array inplace. If an error is raised use numpy
+        resize function to create a new array. Return the array.
+        """
+        try:
+            arr.resize(new_size)
+        except ValueError:
+            msg = ('Resizing a TauP array inplace failed due to the existence'
+                   ' of other references to the array, creating a new array. '
+                   'See Obspy #2280.')
+            warnings.warn(msg)
+            arr = np.resize(arr, new_size)
+        return arr