Changeset 7382:d811ced9a6dd

Timestamp:

11/07/07 08:29:09 (6 years ago)

Author:

Martin Albrecht <malb@…>

Branch:

default

Message:

fix for #1122 (error in libsingular -> givaro conversion)

File:

• sage/libs/singular/singular.pyx (modified) (3 diffs)

sage/libs/singular/singular.pyx

@@ -98 +98 @@
         OUTPUT:
             An Element in GF(q).
-        
+
+        EXAMPLE:
+            sage: K.<a> = GF(5^3)
+            sage: R.<x,y,z> = PolynomialRing(K)
+            sage: K( (4*R(a)^2 + R(a))^3 )
+            a^2
         """
         cdef napoly *z
@@ -104 +109 @@
         cdef int a
         cdef int ret
+        cdef int order
 
         if naIsZero(n):
@@ -113 +119 @@
         a = base.objectptr.sage_generator()
         ret = base.objectptr.zero
-
+        order = base.objectptr.cardinality() - 1
+        
         while z:
             c = base.objectptr.initi(c,<long>napGetCoeff(z))
             e = napGetExp(z,1)
             if e == 0:
-                ret = base.objectptr.add(ret, <int>c, ret)
+                ret = base.objectptr.add(ret, c, ret)
             else:
-                a = e * base.objectptr.sage_generator()
-                ret = base.objectptr.axpy(ret, <int>c, a, ret)
+                a = ( e * base.objectptr.sage_generator() ) % order
+                ret = base.objectptr.axpy(ret, c, a, ret)
             z = napIter(z)
         return (<FiniteField_givaroElement>base._zero_element)._new_c(ret)