betti.cpp

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#include "betti.hpp"
 
#include <iostream>
 
BettiDisplay::BettiDisplay()
    : mLoDegree(0), mHiDegree(0), mHiLength(0), mNLevels(0)
{
  mValues = nullptr;
}
 
BettiDisplay::BettiDisplay(int lodegree, int hidegree, int hilen)
    : mLoDegree(lodegree),
      mHiDegree(hidegree),
      mHiLength(hilen),
      mNLevels(hilen + 1)
{
  int nelems = (hidegree - lodegree + 1) * mNLevels;
  mValues = new int[nelems];
  for (int i = 0; i < nelems; i++) mValues[i] = 0;
}
 
BettiDisplay::BettiDisplay(const BettiDisplay& B)
    : mLoDegree(B.mLoDegree),
      mHiDegree(B.mHiDegree),
      mHiLength(B.mHiLength),
      mNLevels(B.mNLevels)
{
  int nelems = (mHiDegree - mLoDegree + 1) * mNLevels;
  mValues = new int[nelems];
  for (int i = 0; i < nelems; i++) mValues[i] = B.mValues[i];
}
 
void BettiDisplay::swap(BettiDisplay& B)
{
  std::swap(mLoDegree, B.mLoDegree);
  std::swap(mHiDegree, B.mHiDegree);
  std::swap(mHiLength, B.mHiLength);
  std::swap(mNLevels, B.mNLevels);
  std::swap(mValues, B.mValues);
}
 
BettiDisplay& BettiDisplay::operator=(const BettiDisplay& B)
{
  if (this != &B)
    {
      BettiDisplay b(B);
      swap(b);
    }
  return *this;
}
 
BettiDisplay::~BettiDisplay()
{
  delete[] mValues;
  mValues = nullptr;
}
 
void BettiDisplay::resize(int new_lo_degree, int new_hi_degree, int new_length)
{
  if (new_lo_degree == mLoDegree && new_hi_degree == mHiDegree &&
      new_length == mHiLength)
    return;
  BettiDisplay C(new_lo_degree, new_hi_degree, new_length);
  int lodeg = std::max(new_lo_degree, mLoDegree);
  int hideg = std::min(new_hi_degree, mHiDegree);
  int len = std::min(new_length, mHiLength);
  for (int deg = lodeg; deg <= hideg; deg++)
    for (int lev = 0; lev <= len; lev++) C.entry(deg, lev) = entry(deg, lev);
  swap(C);
}
int& BettiDisplay::entry(int deg, int lev)
{
  if (deg < mLoDegree or deg > mHiDegree or lev < 0 or lev > mHiLength)
    {
      std::cout << "Internal error: (" << deg << "," << lev << ") out of range"
                << std::endl;
      exit(1);
    }
  return mValues[lev + mNLevels * (deg - mLoDegree)];
}
 
M2_arrayint BettiDisplay::getBetti() const
{
  return betti_make(mLoDegree, mHiDegree, mHiLength, mValues);
}
 
void BettiDisplay::displayBetti(buffer& o) const
{
  M2_arrayint b = getBetti();
  betti_display(o, b);
}
 
void BettiDisplay::output() const
{
  buffer o;
  displayBetti(o);
  std::cout << o.str() << std::endl;
}
 
M2_arrayint BettiDisplay::betti_make(int lo, int hi, int len, int* bettis)
{
  int d, lev;
  int hi1 = hi + 1;
  int len1 = len + 1;
 
  // Reset 'hi1' to reflect the top degree that occurs
  for (d = hi; d >= lo; d--)
    {
      for (lev = 0; lev <= len; lev++)
        if (bettis[lev + (len + 1) * (d - lo)] > 0)
          {
            hi1 = d;
            break;
          }
      if (hi1 <= hi) break;
    }
  if (hi1 > hi) hi1 = hi;
 
  // Reset 'len1' to reflect the top level that occurs
  for (lev = len; lev >= 0; lev--)
    {
      for (d = lo; d <= hi1; d++)
        if (bettis[lev + (len + 1) * (d - lo)] > 0)
          {
            len1 = lev;
            break;
          }
      if (len1 <= len) break;
    }
  if (len1 > len) len1 = len;
 
  int totallen = (hi1 - lo + 1) * (len1 + 1);
  M2_arrayint result = M2_makearrayint(3 + totallen);
 
  result->array[0] = lo;
  result->array[1] = hi1;
  result->array[2] = len1;
 
  int next = 3;
  for (d = lo; d <= hi1; d++)
    for (lev = 0; lev <= len1; lev++)
      result->array[next++] = bettis[lev + (len + 1) * (d - lo)];
 
  return result;
}
 
void BettiDisplay::betti_display(buffer& o, M2_arrayint ar)
{
  int* a = ar->array;
  int total_sum = 0;
  int lo = a[0];
  int hi = a[1];
  int len = a[2] + 1;
  o << "total  ";
  for (int lev = 0; lev < len; lev++)
    {
      int sum = 0;
      for (int d = lo; d <= hi; d++) sum += a[len * (d - lo) + lev + 3];
      total_sum += sum;
      o.put(sum, 6);
      o << ' ';
    }
  o << " [" << total_sum << "]" << newline;
  for (int d = lo; d <= hi; d++)
    {
      o.put(d, 5);
      o << ": ";
      for (int lev = 0; lev < len; lev++)
        {
          int c = a[len * (d - lo) + lev + 3];
          if (c != 0)
            o.put(c, 6);
          else
            o << "     -";
          o << " ";
        }
      o << newline;
    }
}
 
// Local Variables:
// compile-command: "make -C $M2BUILDDIR/Macaulay2/e "
// indent-tabs-mode: nil
// End: