使用scipy,您正在寻找的功能是scipy.stats.rankdata:
In [13]: import scipy.stats as ss
In [19]: ss.rankdata([3, 1, 4, 15, 92])
Out[19]: array([ 2., 1., 3., 4., 5.])
In [20]: ss.rankdata([1, 2, 3, 3, 3, 4, 5])
Out[20]: array([ 1., 2., 4., 4., 4., 6., 7.])
队伍从1开始,而不是0(如在你的例子),但话又说回来,就是这样R
的rank
功能的作品也是如此。
这是scipy
的rankdata函数的纯Python等效项:
def rank_simple(vector):
return sorted(range(len(vector)), key=vector.__getitem__)
def rankdata(a):
n = len(a)
ivec=rank_simple(a)
svec=[a[rank] for rank in ivec]
sumranks = 0
dupcount = 0
newarray = [0]*n
for i in xrange(n):
sumranks += i
dupcount += 1
if i==n-1 or svec[i] != svec[i+1]:
averank = sumranks / float(dupcount) + 1
for j in xrange(i-dupcount+1,i+1):
newarray[ivec[j]] = averank
sumranks = 0
dupcount = 0
return newarray
print(rankdata([3, 1, 4, 15, 92]))
# [2.0, 1.0, 3.0, 4.0, 5.0]
print(rankdata([1, 2, 3, 3, 3, 4, 5]))
# [1.0, 2.0, 4.0, 4.0, 4.0, 6.0, 7.0]