No, but you can use upside-down floor division:¹
def ceildiv(a, b):
return -(a // -b)
This works because Python’s division operator does floor division (unlike in C, where integer division truncates the fractional part).
Here’s a demonstration:
>>> from __future__ import division # for Python 2.x compatibility
>>> import math
>>> def ceildiv(a, b):
... return -(a // -b)
...
>>> b = 3
>>> for a in range(-7, 8):
... q1 = math.ceil(a / b) # a/b is float division
... q2 = ceildiv(a, b)
... print("%2d/%d %2d %2d" % (a, b, q1, q2))
...
-7/3 -2 -2
-6/3 -2 -2
-5/3 -1 -1
-4/3 -1 -1
-3/3 -1 -1
-2/3 0 0
-1/3 0 0
0/3 0 0
1/3 1 1
2/3 1 1
3/3 1 1
4/3 2 2
5/3 2 2
6/3 2 2
7/3 3 3
Why this instead of math.ceil?
math.ceil(a / b) can quietly produce incorrect results, because it introduces floating-point error. For example:
>>> from __future__ import division # Python 2.x compat >>> import math >>> def ceildiv(a, b): ... return -(a // -b) ... >>> x = 2**64 >>> y = 2**48 >>> ceildiv(x, y) 65536 >>> ceildiv(x + 1, y) 65537 # Correct >>> math.ceil(x / y) 65536 >>> math.ceil((x + 1) / y) 65536 # Incorrect!
In general, it’s considered good practice to avoid floating-point arithmetic altogether unless you specifically need it. Floating-point math has several tricky edge cases, which tends to introduce bugs if you’re not paying close attention. It can also be computationally expensive on small/low-power devices that do not have a hardware FPU.
¹In a previous version of this answer, ceildiv was implemented as return -(-a // b) but it was changed to return -(a // -b) after commenters reported that the latter performs slightly better in benchmarks. That makes sense, because the dividend (a) is typically larger than the divisor (b). Since Python uses arbitrary-precision arithmetic to perform these calculations, computing the unary negation -a would almost always involve equal-or-more work than computing -b.