CoCoA:HowTo:Use Modular Numbers
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Modular Numbers
Question
What's wrong in this?
Use R::=Z/(5)[x]; 5x+2y; 2y ------------------------------- 5=0; FALSE -------------------------------
Moreover this throws an error
Use R::=Z/(5);
Answer
Type(5); INT -------------------------------
5 is an integer, and integers do not depend on the current ring: could you imagine what would happen to a For cycle over Z/(2)? ;-) If you want to use 5 as a modular number you should use this syntax (similar to C/C++)
5 % 5; 0 % 5 -------------------------------
or embed your integer into the polynomial ring
Use R::=Z/(5)[x]; Poly(5); 0 -------------------------------