elsa wrote:
Hi John and others,
sorry about my etiquette errors. As you can tell I'm a newbie, and
appreciate all the help I can get. I'm trying to master this thing
with only the net and a couple of books as tutors.
Here is what I'm running at the interactive prompt:
[snip]
def event():
"""
randomly chooses a birth (prob .3), death (prob .1) or mutation
(prob .1) event
"""
choice = random.random()
if choice <= .3:
event='b'
elif choice <= .4:
event ='d'
elif choice<= .5:
event = 'm'
else:
event = 'None'
return event
[snip]
Here's my line of thought:
Currently, 0 <= choice < 1.0.
If you multiplied the random number by 10 then the probability
thresholds could all be ints, and if you're using ints then 'choice'
could be an index into a list:
event_choices = ['b', 'b', 'b', 'd', 'm'] + ['None'] * 5
which then suggests using random.choice() instead:
def event():
"""
randomly chooses a birth (prob .3), death (prob .1) or mutation (prob
.1) event
"""
return random.choice(event_choices)
and you could put the event code inline instead of in a function, which
saves the cost of a function call.
Incidentally, for a probability of 0.3 the test should be "choice <
0.3", etc, not "choice <= 0.3", etc, although I suspect that you won't
notice any difference in the results! :-)
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