h.trace

来自「强大的数学工具包」· TRACE 代码 · 共 32 行

                               * * * * * * *
                               *   trace   *
                               * * * * * * *

        "trace"
        SYNTAX: X = trace(M)

        First case:   M is an expression whose value is an algebraic 
                      number.
                      X is assigned the trace of M over Q.
        Second case:  M is a square matrix over Z, Q, Z/mZ, GF(p^n),
                      number fields, polynomials over these structures
                      or rational functions over Q.
                      X is assigned the trace of M.
        

        Example 1: (correct)

                trace(NF(A^7))


        Example 2: (incorrect)

                trace(NF(x))

_ERR_NR_034_trace_             


        Example 3: (correct)
   
                trace({{MOD(3*x+4),MOD(2)}{MOD(x^3-2),MOD(3)}})