[R] For Loop
Duncan Murdoch
murdoch@dunc@n @end|ng |rom gm@||@com
Sun Sep 23 21:42:28 CEST 2018
On 23/09/2018 3:31 PM, Jeff Newmiller wrote:
[lots of good stuff deleted]
> Vectorize is
> syntactic sugar with a performance penalty.
[More deletions.]
I would say Vectorize isn't just "syntactic sugar". When I use that
term, I mean something that looks nice but is functionally equivalent.
However, Vectorize() really does something useful: some functions (e.g.
outer()) take other functions as arguments, but they assume the argument
is a vectorized function. If it is not, they fail, or generate garbage
results. Vectorize() is designed to modify the interface to a function
so it acts as if it is vectorized.
The "performance penalty" part of your statement is true. It will
generally save some computing cycles to write a new function using a for
loop instead of using Vectorize(). But that may waste some programmer time.
Duncan Murdoch
(writing as one of the authors of Vectorize())
P.S. I'd give an example of syntactic sugar, but I don't want to bruise
some other author's feelings :-).
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