大约有 48,000 项符合查询结果（耗时：0.0268秒） [XML]
What are the differences between json and simplejson Python modules?
...
394
json is simplejson, added to the stdlib. But since json was added in 2.6, simplejson has the adv...
“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
...
answered Mar 27 '11 at 4:01
Winston EwertWinston Ewert
39.1k1010 gold badges6262 silver badges7878 bronze badges
...
Calculate difference in keys contained in two Python dictionaries
...
234
You can use set operations on the keys:
diff = set(dictb.keys()) - set(dicta.keys())
Here is ...
Can dplyr package be used for conditional mutating?
...f %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with if_else; howev...
How to test valid UUID/GUID?
...
439
Currently, UUID's are as specified in RFC4122. An often neglected edge case is the NIL UUID, n...
What is the optimal Jewish toenail cutting algorithm?
...ort ifilter, permutations
validseqs = ifilter(isValid, permutations([1,2,3,4,5]))
for i in validseqs:
print i
(1, 3, 5, 2, 4)
(1, 4, 2, 5, 3)
(2, 4, 1, 3, 5)
(2, 4, 1, 5, 3)
(2, 5, 3, 1, 4)
(3, 1, 4, 2, 5)
(3, 1, 5, 2, 4)
(3, 5, 1, 4, 2)
(3, 5, 2, 4, 1)
(4, 1, 3, 5, 2)
(4, 2, 5, 1, 3)
(4, 2, 5,...
Reduce, fold or scan (Left/Right)?
...e first argument res of our binary operator minus:
val xs = List(1, 2, 3, 4)
def minus(res: Int, x: Int) = {
println(s"op: $res - $x = ${res - x}")
res - x
}
xs.reduceLeft(minus)
// op: 1 - 2 = -1
// op: -1 - 3 = -4 // de-cumulates value -1 in *first* operator arg `res`
// op: -4 - 4 = -8
//...
All combinations of a list of lists
...
449
you need itertools.product:
>>> import itertools
>>> a = [[1,2,3],[4,5,6],[...
Print all but the first three columns
...tion that does not add extra leading or trailing whitespace:
awk '{ for(i=4; i<NF; i++) printf "%s",$i OFS; if(NF) printf "%s",$NF; printf ORS}'
### Example ###
$ echo '1 2 3 4 5 6 7' |
awk '{for(i=4;i<NF;i++)printf"%s",$i OFS;if(NF)printf"%s",$NF;printf ORS}' |
tr ' ' '-'
4-5-6-7
Sudo...