TSparseVec operator - (const TSparseVec &a, const TSparseVec &b)
{
Assert(a.Elts() == b.Elts(), "(SparseVec::-) Vec sizes don't match");
TSparseVec result(a.Elts());
Int i, j;
for (i = 0, j = 0; ; )
if (a[i].index == b[j].index)
{
if (a[i].index == VL_SV_MAX_INDEX)
break;
result.AddElt(a[i].index, a[i].elt - b[j].elt); // -
i++;
j++;
}
else if (a[i].index < b[j].index)
{ result.AddNZElt(a[i]); i++; }
else
{ result.AddNZElt(b[j].index, -b[j].elt); j++; }
result.End();
return(result);
}
TSparseVec operator + (const TSparseVec &a, const TSparseVec &b)
{
Assert(a.Elts() == b.Elts(), "(SparseVec::+) Vec sizes don't match");
TSparseVec result(a.Elts());
Int i, j;
// Step through a and b in parallel
for (i = 0, j = 0; ; )
if (a[i].index == b[j].index)
{
// We have two elements at the same index.
// Are we at the end of both arrays?
if (a[i].index == VL_SV_MAX_INDEX)
break;
// If not, add the result
result.AddElt(a[i].index, a[i].elt + b[j].elt); // +
i++;
j++;
}
else if (a[i].index < b[j].index)
// result[x] = a[i] + 0
{ result.AddNZElt(a[i]); i++; }
else
// result[x] = b[j] + 0
{ result.AddNZElt(b[j]); j++; }
result.End();
return(result);
}
TSparseVec operator * (const TSparseVec &v, TVReal s)
{
TSparseVec result(v.Elts());
Int i;
for (i = 0; i < v.NumItems() - 1; i++)
result.AddElt(v[i].index, s * v[i].elt);
result.End();
return(result);
}
TSparseVec operator - (const TSparseVec &v)
{
TSparseVec result(v.Elts());
Int i;
for (i = 0; i < v.NumItems() - 1; i++)
result.AddNZElt(v[i].index, -v[i].elt);
result.End();
return(result);
}
TVReal dot(const TSparseVec &a, const TVec &b)
{
Assert(a.Elts() == b.Elts(), "(SparseVec::dot) Vec sizes don't match");
TMReal sum = vl_zero;
Int i;
for (i = 0; i < a.NumItems() - 1; i++)
sum += a[i].elt * b[a[i].index];
return(sum);
}
TVReal dot(const TSparseVec &a, const TSparseVec &b)
{
Assert(a.Elts() == b.Elts(), "(SparseVec::dot) Vec sizes don't match");
TMReal sum = vl_zero;
TSVIter j(a);
Int i;
for (i = 0; i < b.NumItems() - 1; i++)
if (j.IncTo(b[i].index))
sum += j.Data() * b[i].elt;
return(sum);
}
TSparseVec operator / (const TSparseVec &a, const TSparseVec &b)
{
Assert(a.Elts() == b.Elts(), "(SparseVec::/) Vec sizes don't match");
TSparseVec result(a.Elts());
TSVIter j(a);
Int i;
for (i = 0; i < b.NumItems() - 1; i++)
if (j.IncTo(b[i].index))
result.AddElt(b[i].index, j.Data() / b[i].elt);
result.End();
return(result);
}
TSparseVec operator * (const TSparseVec &v, const TSparseMat &m) // v * m
{
Assert(v.Elts() == m.Rows(), "(Mat::v*m) vector/matrix sizes don't match");
TMSparseVec temp(m.Cols());
TSparseVec result(m.Cols());
Int i;
TSVIter j(v);
TMSVIter k;
temp = vl_zero;
// v * M = v[0] * m[0] + v[1] * m[1] + ...
for (i = 0; i < m.Rows(); i++)
{
j.Inc(i);
if (j.Exists(i))
temp += m[i] * j.Data();
}
result.SetNumElts(temp.Elts());
result.Begin();
for (k.Begin(temp.Elts()); !k.AtEnd(); k.Inc())
result.AddNZElt(k.Index(), k.Data());
result.End();
return(result);
}
TSparseMat oprod(const TSparseVec &a, const TSparseVec &b)
// returns outerproduct of a and b: a * trans(b)
{
TSparseMat result;
TSVIter i;
result.SetSize(a.Elts(), b.Elts());
result = vl_0;
for (i.Begin(a); !i.AtEnd(); i.Inc())
{
result[i.Index()] = b;
result[i.Index()] *= i.Data();
}
return(result);
}
Bool operator == (const TSparseVec &a, const TSparseVec &b)
{
Assert(a.Elts() == b.Elts(), "(SparseVec::==) Vec sizes don't match");
if (a.NumItems() != b.NumItems())
return(false);
else
{
Int i;
for (i = 0; i < a.NumItems(); i++)
if (a[i] != b[i])
return(false);
return(true);
}
}
TVReal sqrlen(const TSparseVec &v)
{
TVReal sum = vl_zero;
Int i;
for (i = 0; i < v.NumItems() - 1; i++)
sum += sqrlen(v[i].elt);
return(sum);
}
TSparseVec operator * (const TSparseMat &m, const TSparseVec &v)
{
Assert(m.Cols() == v.Elts(), "(SparseMat::m*v) matrix and vector sizes don't match");
Int i;
TSparseVec result(m.Rows());
for (i = 0; i < m.Rows(); i++)
result.AddElt(i, dot(m[i], v));
result.End();
return(result);
}
TMSparseVec operator * (const TSparseVec &v, const TSparseMat &m) // v * m
{
Assert(v.Elts() == m.Rows(), "(Mat::v*m) vector/matrix sizes don't match");
TMSparseVec result(m.Cols());
Int i;
TSVIter j(v);
result = vl_zero;
// v * M = v[0] * m[0] + v[1] * m[1] + ...
for (i = 0; i < m.Rows(); i++)
{
j.Inc(i);
if (j.Exists(i))
result += m[i] * j.Data();
}
return(result);
}
