How do I suppress the following ?
Warning messages:
1: the condition has length > 1 and only the first element will be used
in: if (strike == forward) atmvol(forward, t, alpha, beta, rho, upsilon)
else {
2: the condition has length > 1 and only the first element will be used
in: if (x(z) == 0) 1 else z/x(z)