recall a function

[Han]

Any symbolic manipulation is going to require the CAS, with exception for a few commands. To get around this, you could try:

Code:

EXPORT gamma_cdf(k,t,n)
BEGIN
local f:= int((X^(k-1)*e^(-X/t))/(t^k*Gamma(k)), X, 0, n);
return f;
END ;

Sometimes it is possible to also quote an expression (e.g. 'X' vs X) although in HPPPL, quoted objects are still (generally) evaluated.