recursive method not reaching base case

i was working on implementing the original supermemo algorithm (see
http://www.supermemo.com/english/ol/sm2.htm for a description of it) in
a class, and i'd just finished up the first draft. it works for
repetitions one and two, but on repetition three (you must manually
increment item.reps.) or higher it recurses until it reaches the limit.
can someone point out what i'm doing wrong here?

here's the code:
class item:
def __init__(self, key, value):
self.key = key
self.value = value
self.reps = 1
self.ef = 2.5
def interval(self):
if(self.reps==1):
return 2
if(self.reps==2):
return 6
return (self.interval() - 1) * self.ef

possibilitybox

possibilitybox wrote:
> i was working on implementing the original supermemo algorithm (see
> http://www.supermemo.com/english/ol/sm2.htm for a description of it) in
> a class, and i'd just finished up the first draft. it works for
> repetitions one and two, but on repetition three (you must manually
> increment item.reps.) or higher it recurses until it reaches the limit.
> can someone point out what i'm doing wrong here?
>
> here's the code:
> class item:
> def __init__(self, key, value):
> self.key = key
> self.value = value
> self.reps = 1
> self.ef = 2.5
> def interval(self):
> if(self.reps==1):
> return 2
> if(self.reps==2):
> return 6
> return (self.interval() - 1) * self.ef

You're not changing self.reps at all, so interval() keeps getting called
over and over again with self.reps == 3.

--
Robert Kern


"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter

Robert Kern

so obvious! thank you for helping me there. i knew it was simple, i
just couldn't catch it.

possibilitybox