By the way--the user documentation says that numerval allows for non-floats:
(%i1) numerval(%z, (1+sqrt(7))/2);
(%o1) [%z]
(%i2) 5*%z + 2013,numer;
(%o2) 2022.114378277661
(%i3) ?? numerval;
-- Function: numerval (<x_1>, <expr_1>, ..., <var_n>, <expr_n>)
Declares the variables `x_1', ..., <x_n> to have numeric values
equal to `expr_1', ..., `expr_n'. The numeric value is evaluated
and substituted for the variable in any expressions in which the
variable occurs if the `numer' flag is `true'. See also `ev'.
The expressions `expr_1', ..., `expr_n' can be any expressions,
not necessarily numeric.
(%o3) true
--Barton
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