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MapDown |
Syntax |
MapDown(F:POLY):RAT or ZMOD |
Summary |
convert a constant polynomial to a number |
Description |
This function converts a constant polynomial to the equivalent coefficient. If the argument is not a constant polynomial, an error is signalled. |
Example |
Use Q[x,y,z]; Type((x+1)^2 - x*(x+2)); -- value is seen as a polynomial POLY ------------------------------- MapDown((x+1)^2 - x*(x+2)); -- attempt to map down to the coeff ring 1 ------------------------------- Type(It); -- value is now simply a coefficient RAT ------------------------------- MapDown((x+1)^2 - x^2); -- 2*x + 1 is not a coefficient ERROR: Cannot MapDown non-const poly CONTEXT: Error("Cannot MapDown non-const poly") ------------------------------- |