public static MathObject CoefficientGpe(this MathObject u, MathObject x, int j)
{
if (!(u is Sum))
{
Tuple <MathObject, int> f = u.CoefficientMonomialGpe(x);
if (f == null)
{
return(null);
}
return(f.Item2 == j ? f.Item1 : 0);
}
if (u == x)
{
return(j == 1 ? 1 : 0);
}
MathObject c = 0;
foreach (Tuple <MathObject, int> f in ((Sum)u).elts.Select(elt => elt.CoefficientMonomialGpe(x)))
{
if (f == null)
{
return(null);
}
if (f.Item2 == j)
{
c = c + f.Item1;
}
}
return(c);
}
public static MathObject CoefficientGpe(this MathObject u, MathObject x, int j)
{
if (!(u is Sum))
{
var f = u.CoefficientMonomialGpe(x);
if (f == null)
{
return(null);
}
if (f.Item2 == j)
{
return(f.Item1);
}
return(0);
}
if (u == x)
{
return(j == 1 ? 1 : 0);
}
var c = (MathObject)0;
foreach (var elt in (u as Sum).elts)
{
var f = elt.CoefficientMonomialGpe(x);
if (f == null)
{
return(null);
}
if (f.Item2 == j)
{
c = c + f.Item1;
}
}
return(c);
}
