Changeset cb7b21 in git

Timestamp:

Jan 7, 2014, 5:51:07 PM (10 years ago)

Author:

Martin Lee <martinlee84@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

7c43417b3c0a11646757be1dbd5877c7b19d0459

Parents:

49ba0963eace9d5fafa517dc5e9b39eb0ed0a096

git-author:

Martin Lee <martinlee84@web.de>2014-01-07 17:51:07+01:00

git-committer:

Martin Lee <martinlee84@web.de>2014-01-20 16:45:04+01:00

Message:

chg: new function to get coeffs over extension with FLINT

Location:

factory

Files:

• facFqBivarUtil.cc (modified) (2 diffs)
• facFqBivarUtil.h (modified) (2 diffs)

factory/facFqBivarUtil.cc

@@ -31 +31 @@
 #include "facHensel.h"
 #include "facMul.h"
+
+#ifdef HAVE_FLINT
+#include "FLINTconvert.h"
+#endif
 
 TIMING_DEFINE_PRINT(fac_log_deriv_div)
@@ -698 +702 @@
 #endif
 
+#ifdef HAVE_FLINT
+CFArray
+getCoeffs (const CanonicalForm& G, const int k, const int l, const int degMipo,
+           const Variable& alpha, const CanonicalForm& evaluation,
+           const nmod_mat_t M)
+{
+  ASSERT (G.isUnivariate() || G.inCoeffDomain(), "univariate input expected");
+  CanonicalForm F= G (G.mvar() - evaluation, G.mvar());
+  if (F.isZero())
+    return CFArray ();
+
+  Variable y= Variable (2);
+  F= F (power (y, degMipo), y);
+  F= F (y, alpha);
+
+  nmod_poly_t FLINTF;
+  nmod_mat_t MFLINTF, mulResult;
+  nmod_mat_init (MFLINTF, l*degMipo, 1, getCharacteristic());
+  nmod_mat_init (mulResult, l*degMipo, 1, getCharacteristic());
+
+  convertFacCF2nmod_poly_t (FLINTF, F);
+
+  slong i;
+
+  for (i= 0; i < FLINTF->length; i++)
+    nmod_mat_entry (MFLINTF, i, 0)= FLINTF->coeffs[i];
+
+  for (; i < MFLINTF->r; i++)
+    nmod_mat_entry (MFLINTF, i, 0)= UWORD(0);
+
+  nmod_mat_mul (mulResult, M, MFLINTF);
+
+  F= 0;
+  for (i= 0; i < mulResult->r; i++)
+    F += CanonicalForm ((long) nmod_mat_entry (mulResult, i, 0))*power (y, i);
+
+  nmod_mat_clear (MFLINTF);
+  nmod_mat_clear (mulResult);
+
+  if (degree (F, 2) < k)
+    return CFArray();
+
+  CFArray result= CFArray (degree (F) - k + 1);
+
+  CFIterator j= F;
+  for (int i= degree (F); i >= k; i--)
+  {
+    if (j.exp() == i)
+    {
+      result [i - k]= j.coeff();
+      j++;
+      if (!j.hasTerms())
+        return result;
+    }
+    else
+      result[i - k]= 0;
+  }
+  return result;
+}
+#endif
+
 int * computeBounds (const CanonicalForm& F, int& n, bool& isIrreducible)
 {

factory/facFqBivarUtil.h

@@ -21 +21 @@
 #ifdef HAVE_NTL
 #include "NTLconvert.h"
+#endif
+
+#ifdef HAVE_FLINT
+#include "FLINTconvert.h"
 #endif
 
@@ -269 +273 @@
 #endif
 
+#ifdef HAVE_FLINT
+/// extract coefficients of \f$ x^i \f$ for \f$i\geq k\f$ where \f$ x \f$ is
+/// a variable of level 1
+///
+/// @return coefficients of \f$ x^i \f$ for \f$i\geq k\f$
+/// @sa {getCoeffs (const CanonicalForm&, const int, const Variable& alpha),
+/// getCoeffs (const CanonicalForm&, const int)}
+CFArray
+getCoeffs (const CanonicalForm& F,         ///< [in] compressed bivariate poly
+           const int k,                    ///< [in] some int
+           const int l,                    ///< [in] precision
+           const int degMipo,              ///< [in] degree of minimal poly
+           const Variable& alpha,          ///< [in] algebraic variable
+           const CanonicalForm& evaluation,///< [in] evaluation point
+           const nmod_mat_t M              ///< [in] bases change matrix
+          );
+#endif
+
 /// write A into M starting at row startIndex
 void