Python: Mapping from intervals to values
import bisect
bisect.bisect_left([100,300,500,800,1000], p)
here the docs: bisect
It is indeed quite horrible. Without a requirement to have no hardcoding, it should have been written like this:
if p <= 100:
return 0
elif p <= 300:
return 1
elif p <= 500:
return 2
elif p <= 800:
return 3
elif p <= 1000:
return 4
else:
return 5
Here are examples of creating a lookup function, both linear and using binary search, with the no-hardcodings requirement fulfilled, and a couple of sanity checks on the two tables:
def make_linear_lookup(keys, values):
assert sorted(keys) == keys
assert len(values) == len(keys) + 1
def f(query):
return values[sum(1 for key in keys if query > key)]
return f
import bisect
def make_bisect_lookup(keys, values):
assert sorted(keys) == keys
assert len(values) == len(keys) + 1
def f(query):
return values[bisect.bisect_left(keys, query)]
return f
You could try a take on this:
def check_mapping(p):
mapping = [(100, 0), (300, 1), (500, 2)] # Add all your values and returns here
for check, value in mapping:
if p <= check:
return value
print check_mapping(12)
print check_mapping(101)
print check_mapping(303)
produces:
0
1
2
As always in Python, there will be any better ways to do it.