interred gives "characteristic too large"

[steenpass]

> ring r = (536870923,t), x, dp;
> ideal i = x, x+1;
> interred(i);
   ? characteristic is too large(max is 2^29)
   ? characteristic is too large(max is 2^29)
   ? error occurred in or before STDIN line 3: `interred(i);`

This does not happen without the parameter:

> ring s = 536870923, x, dp;
> ideal i = x, x+1;
> interred(i);
_[1]=1
> 

I don't see any substantial reason for this. Please note that interred() is used in primdecGTZ(), hence this issue is important when it comes to modular primary decomposition.

[hannes]

Computing with rational functions involves (sometimes) computations of gcd of polynomials, which belongs to factory. The limit mentioned is really the limit of factory and only leads to an error, if the calls to gcd really occur.

This limit is well documented and can not be easily changed.

Without the parameter, factory is not involved.