internal Combo(Unit a, String op, Unit b)
{
this.a = a; this.op = op; this.b = b;
}
private static Unit findMult(Unit a, Unit b)
{
// compute dim/scale of a * b
Dimension dim = a.m_dim.add(b.m_dim).intern();
double scale = a.m_scale * b.m_scale;
// find all the matches
Unit[] matches = match(dim, scale);
if (matches.Length == 1) return matches[0];
// right how our technique for resolving multiple matches is lame
string expectedName = a.name() + "_" + b.name();
for (int i=0; i<matches.Length; ++i)
if (matches[i].name() == expectedName)
return matches[i];
// for now just give up
throw Err.make("Cannot match to db: " + a + " * " + b).val;
}
//////////////////////////////////////////////////////////////////////////
// Arithmetic
//////////////////////////////////////////////////////////////////////////
public Unit mult(Unit b)
{
lock (m_combos)
{
Combo key = new Combo(this, "*", b);
Unit r = (Unit)m_combos[key];
if (r == null)
{
r = findMult(this, b);
m_combos[key] = r;
}
return r;
}
}
public Unit findDiv(Unit a, Unit b)
{
// compute dim/scale of a / b
Dimension dim = a.m_dim.subtract(b.m_dim).intern();
double scale = a.m_scale / b.m_scale;
// find all the matches
Unit[] matches = match(dim, scale);
if (matches.Length == 1) return matches[0];
// right how our technique for resolving multiple matches is lame
string expectedName = a.name() + "_per_" + b.name();
for (int i=0; i<matches.Length; ++i)
if (matches[i].name().Contains(expectedName))
return matches[i];
// for now just give up
throw Err.make("Cannot match to db: " + a + " / " + b).val;
}
public Unit div(Unit b)
{
lock (m_combos)
{
Combo key = new Combo(this, "/", b);
Unit r = (Unit)m_combos[key];
if (r == null)
{
r = findDiv(this, b);
m_combos[key] = r;
}
return r;
}
}
//////////////////////////////////////////////////////////////////////////
// Conversion
//////////////////////////////////////////////////////////////////////////
public double convertTo(double scalar, Unit to)
{
if (m_dim != to.m_dim) throw Err.make("Incovertable units: " + this + " and " + to).val;
return ((scalar * this.m_scale + this.m_offset) - to.m_offset) / to.m_scale;
}
