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Is inject the same thing as reduce in ruby?
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edited May 9 '14 at 7:03
answered Dec 11 '12 at 3:44
Zac...
How to return multiple lines JSX in another return statement in React?
... the tags as function calls (see docs). Then the first one becomes:
{[1,2,3].map(function (n) {
return React.DOM.p(...);
})}
And the second one:
{[1,2,3].map(function (n) {
return (
React.DOM.h3(...)
React.DOM.p(...)
)
})}
It should now be clear that the second snippet doesn't re...
Split a List into smaller lists of N size
...List<float[]>> SplitList(List<float[]> locations, int nSize=30)
{
var list = new List<List<float[]>>();
for (int i = 0; i < locations.Count; i += nSize)
{
list.Add(locations.GetRange(i, Math.Min(nSize, locations.Count - i)));
}
...
What is the easiest way to push an element to the beginning of the array?
...
390
What about using the unshift method?
ary.unshift(obj, ...) → ary
Prepends objects to t...
Leading zeros for Int in Swift
...
703
Assuming you want a field length of 2 with leading zeros you'd do this:
import Foundation
for ...
Rails 3 migrations: Adding reference column?
If I create a new rails 3 migration with (for example)
10 Answers
10
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How to apply shell command to each line of a command output?
...
pixatlazaki
41355 silver badges1818 bronze badges
answered Apr 26 '10 at 3:34
Michael MrozekMichael Mrozek
...
Filtering a list based on a list of booleans
...se]
>>> list(compress(list_a, fil))
[1, 4]
Timing comparisons(py3.x):
>>> list_a = [1, 2, 4, 6]
>>> fil = [True, False, True, False]
>>> %timeit list(compress(list_a, fil))
100000 loops, best of 3: 2.58 us per loop
>>> %timeit [i for (i, v) in zip(list...
Printing 1 to 1000 without loop or conditionals
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1
2
3
4
Next
785
votes
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cartesian product in pandas
...import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here...