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How is “int* ptr = int()” value initialization not illegal?
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Sample random rows in dataframe
... X2
1 0.7091409 -1.4061361
2 -1.1334614 -0.1973846
3 2.3343391 -0.4385071
4 -0.9040278 -0.6593677
5 0.4180331 -1.2592415
6 0.7572246 -0.5463655
7 -0.8996483 0.4231117
8 -1.0356774 -0.1640883
9 -0.3983045 0.7157506
10 -0.9060305 2.3234110
Then select some rows at random:
> df[s...
Global access to Rake DSL methods is deprecated
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Delete element in a slice
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flornquake
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answered Jul 29 '14 at 21:47
davedave
46.2...
Determine the data types of a data frame's columns
...is makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
@Wilmer E Henao H's solution is very streamlined:
sapply(my.data, class)
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Find XOR of all numbers in a given range
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Shuffle two list at once with same order
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answered Apr 25 '14 at 9:45
sshashank124sshashank124
26.6k77 gold badges5353 silver badges6666 bronze badges
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Difference between exit(0) and exit(1) in Python
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What is the best way to compute trending topics or tags?
...rn (obs - avg) / std
Sample Output
>>> zscore(12, [2, 4, 4, 4, 5, 5, 7, 9])
3.5
>>> zscore(20, [21, 22, 19, 18, 17, 22, 20, 20])
0.0739221270955
>>> zscore(20, [21, 22, 19, 18, 17, 22, 20, 20, 1, 2, 3, 1, 2, 1, 0, 1])
1.00303599234
>>> zscore(2, [21, 22, 19, 18...