(define sumi
(lambda (term a next b)
(define iter
(lambda (a result)
(if (> a b)
result
(iter (next a) (+ result (term a))))))
(iter a 0)))
chez和ikarus的表现完全不一样..
chez:
> (time (sum (lambda (x) (* 2 x)) 0 (lambda (x) (+ x 1)) 3800011))
(time (sum (lambda (...) ...) ...))
65 collections
1176 ms elapsed cpu time, including 322 ms collecting
1177 ms elapsed real time, including 318 ms collecting
275239064 bytes allocated, including 267307688 bytes reclaimed
14440087400132> (time (sumi (lambda (x) (* 2 x)) 0 (lambda (x) (+ x 1)) 3800011))
(time (sumi (lambda (...) ...) ...))
15 collections
932 ms elapsed cpu time, including 3 ms collecting
934 ms elapsed real time, including 5 ms collecting
60092864 bytes allocated, including 146771696 bytes reclaimed
14440087400132
迭代不迭代差别不大..
相反,ikarus很有差别
> (time (sum (lambda (x) (* 2 x)) 0 (lambda (x) (+ x 1)) 3800011))
running stats for (sum (lambda (x) (* 2 x)) 0 (lambda (x) (+ x 1)) 3800011):
29 collections
6600 ms elapsed cpu time, including 5740 ms collecting
6762 ms elapsed real time, including 6156 ms collecting
119417416 bytes allocated
14440087400132
> (time (sumi (lambda (x) (* 2 x)) 0 (lambda (x) (+ x 1)) 3800011))
running stats for (sumi (lambda (x) (* 2 x)) 0 (lambda (x) (+ x 1)) 3800011):
14 collections
460 ms elapsed cpu time, including 248 ms collecting
513 ms elapsed real time, including 365 ms collecting
60429480 bytes allocated
14440087400132
