c = gftrunc(a)
truncates a row vector, a, by removing nonsignificant high-order zeros
at the end of a If a(k) = 0
whenever k>d+1, the polynomial has
degree d. The row vector c omits these high-order
zeros and thus has length d+1.
Truncated coefficients of GF(p) polynomial, returned as a numeric row vector with
the trailing zeros removed. Zeros are removed only from the end of the row-vector, not
from the beginning or middle.