Re: init

Rob Thorpe wrote:
In lisp I would do:-
(map 'vector #'(lambda (cp) (+ cp (/ halfwidth 2))) centerpoint)

Which does the same as the perl Logan Shaw posted.
Can't you just do the same in OCaml?

Initialising a new array is probably the best alternative:

Array.init 3 (fun i -> centerpt.(i) +. halfwidth /. 2.)

You can also replace the elements in-place, as you probably would in C (for
extra speed):

for i=0 to 2 do
boxcenter.(i) <- centerpt.(i) +. halfwidth /. 2.
done;

I often use an implicit integer range data structure to replace loops:

iter (fun i -> boxcenter.(i) <- centerpt.(i) +. halfwidth /. 2.) 0 3

In reality, of course, I'd write a Vec3 module and just do something like:

centerpt +| Vec3.of (halfwidth /. 2.)

--
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
http://www.ffconsultancy.com/products/ocaml_for_scientists/chapter1.html
.

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