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How to find the sum of an array of numbers
Given an array [1, 2, 3, 4] , how can I find the sum of its elements? (In this case, the sum would be 10 .)
43 Answers
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What are the correct version numbers for C#?
...numbers for C#? What came out when? Why can't I find any answers about C# 3.5 ?
12 Answers
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Selecting data frame rows based on partial string match in a column
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3 Answers
3
Active
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How do I detect what .NET Framework versions and service packs are installed?
A similar question was asked here , but it was specific to .NET 3.5. Specifically, I'm looking for the following:
13 Answe...
Add Variables to Tuple
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388
Tuples are immutable; you can't change which variables they contain after construction. Howeve...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
....drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...
Bootstrap 3 offset on right not left
In regards to BS 3 if I wanted just a narrow column of content on the right I might use an offset class of 9 and a column of 3.
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List comprehension: Returning two (or more) items for each item
...: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_iterable((f(x), g(x)) for x in range(3)))',...
Most popular screen sizes/resolutions on Android phones [closed]
...king for.
– dfetter88
Jun 7 '11 at 23:07
21
That link says nothing of how common a resolution is....