S-plus question about length of data

[ToxicBug]

Hello, I'm trying to figure out how to program the Exponential Integral function, and then make it compute values for a vector of data.

I have this:

expint <- function(s){ 
     integrand <- function(x) {exp(x)/x} 
     integrate(integrand, lower = -Inf, upper = s)$integral
}

if I put expint(-1) then it works, but it doesn't work if I put expint(vectorofvalues), it gives me the following error:

Warning messages:
1: Condition has 72 elements: only the first used in: e1 && e2
2: Condition has 72 elements: only the first used in: e1 || e2
Problem in bound + (sgn * (1 - nodes))/nodes: length of longer operand (72) should be a multiple of length of shorter (15)

Anyone know what I need to change for it to work with vectors?

 

[Greg Bernhardt]

It looks like you need to make sure the length of your vector is a multiple of 15. You might also want to look into the "condition has 72 elements" warning, as that could be related to the error you are getting. If you can provide more information about what your vector is and how it is being used, it may help other users give you more specific advice.