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Pandas index column title or name
...index name.
– Piotr Migdal
Apr 11 '15 at 20:37
14
it should be possible to specify index name at ...
Is there an equivalent for the Zip function in Clojure Core or Contrib?
...
(map vector '(1 2 3) '(4 5 6))
does what you want:
=> ([1 4] [2 5] [3 6])
Haskell needs a collection of zipWith (zipWith3, zipWith4, ...) functions, because they all need to be of a specific type; in particular, the number of input lists they...
pandas: filter rows of DataFrame with operator chaining
...the boolean index.
In [96]: df
Out[96]:
A B C D
a 1 4 9 1
b 4 5 0 2
c 5 5 1 0
d 1 3 9 6
In [99]: df[(df.A == 1) & (df.D == 6)]
Out[99]:
A B C D
d 1 3 9 6
If you want to chain methods, you can add your own mask method and use that one.
In [90]: def mask(df, ke...
Assign multiple columns using := in data.table, by group
...1 hi hello
# 2: 2 2 hi hello
# 3: 3 3 hi hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 col2 mean sum
# 1: 1 1 hi hello 2.5 5
# 2: 2 2 hi hello 3.5 7
# 3: 3 3 hi hello 4.5 9
# 4: 1 4 h...
Most popular screen sizes/resolutions on Android phones [closed]
...
GrekzGrekz
1,5541414 silver badges1717 bronze badges
...
Transpose list of lists
...
355
How about
map(list, zip(*l))
--> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
For python 3.x users c...
For each row return the column name of the largest value
...ples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than using apply might be max.col:
colnames(DF)[max.col(DF,ties.method="first")]
#[1] "V3" "V1" "V2"
...where ties.method can be a...
Selecting with complex criteria from pandas.DataFrame
... range(10)]})
>>> df
A B C
0 9 40 300
1 9 70 700
2 5 70 900
3 8 80 900
4 7 50 200
5 9 30 900
6 2 80 700
7 2 80 400
8 5 80 300
9 7 70 800
We can apply column operations and get boolean Series objects:
>>> df["B"] > 50
0 False
1 True...
Index all *except* one item in python
...
115
For a list, you could use a list comp. For example, to make b a copy of a without the 3rd eleme...
Getting key with maximum value in dictionary?
...
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