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What is the difference between ~> and >= when specifying rubygem in Gemfile?
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edited Feb 5 '14 at 23:13
answered Nov 27 '10 at 17:33
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Bomb dropping algorithm
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edited Mar 9 '13 at 8:46
community wiki
4 r...
How can I create a Set of Sets in Python?
...m the following list of lists:
t = [[], [1, 2], [5], [1, 2, 5], [1, 2, 3, 4], [1, 2, 3, 6]]
you can create your set in the following way:
t1 = set(frozenset(i) for i in t)
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Python set to list
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245
Your code does work (tested with cpython 2.4, 2.5, 2.6, 2.7, 3.1 and 3.2):
>>> a = se...
Split delimited strings in a column and insert as new rows [duplicate]
... of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length)), V2 = unlist(...
Get column index from column name in python pandas
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Sure, you can use .get_loc():
In [45]: df = DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [3,4,5]})
In [46]: df.columns
Out[46]: Index([apple, orange, pear], dtype=object)
In [47]: df.columns.get_loc("pear")
Out[47]: 2
although to be honest I do...
“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
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answered Mar 27 '11 at 4:01
Winston EwertWinston Ewert
39.1k1010 gold badges6262 silver badges7878 bronze badges
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Get Android API level of phone currently running my application [duplicate]
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4 Answers
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What would cause an algorithm to have O(log log n) complexity?
...t down to 1? If we do this, we get
65,536 / 2 = 32,768
32,768 / 2 = 16,384
16,384 / 2 = 8,192
8,192 / 2 = 4,096
4,096 / 2 = 2,048
2,048 / 2 = 1,024
1,024 / 2 = 512
512 / 2 = 256
256 / 2 = 128
128 / 2 = 64
64 / 2 = 32
32 / 2 = 16
16 / 2 = 8
8 / 2 = 4
4 / 2 = 2
2 / 2 = 1
This process takes 16 steps...