# HG changeset patch
# User Julian Rueth <julian.rueth@gmail.com>
# Date 1348669702 0
# Node ID 7ffe38b585130075a207b9069d9f0d72c0e231d6
# Parent 698ec14c513f99fa5a3a7aeca982cc14fd249a89
Trac 13439: added a stopgap warning about incorrect xgcd computations
diff git a/sage/rings/polynomial/padics/polynomial_padic_capped_relative_dense.py b/sage/rings/polynomial/padics/polynomial_padic_capped_relative_dense.py
a

b

class Polynomial_padic_capped_relative_dense(Polynomial_generic_domain): 
972  972  # raise NotImplementedError 
973  973  
974  974  def xgcd(self, right): 
 975  from sage.misc.stopgap import stopgap 
 976  stopgap("Extended gcd computations over padic fields are performed using the standard Euclidean algorithm which might produce mathematically incorrect results in some cases.", 13439) 
 977  
975  978  return self._xgcd(right) 
976  979  
977  980  #def discriminant(self): 
diff git a/sage/rings/polynomial/polynomial_element_generic.py b/sage/rings/polynomial/polynomial_element_generic.py
a

b

class Polynomial_padic_field_dense(Polynomial_padic_generic_dense, Polynomial_ge 
781  781  else: 
782  782  return self.base_ring()(0) 
783  783  
784   def _xgcd(self, other): 
785   H = Polynomial_generic_dense_field._xgcd(self, other) 
786   c = ~H[0].leading_coefficient() 
787   return c * H[0], c * H[1], c * H[2] 
788   
789   
790  784  class Polynomial_padic_ring_lazy_dense(Polynomial_padic_ring_dense): 
791  785  pass 
792  786  