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Base64 length calculation?
...
217
Each character is used to represent 6 bits (log2(64) = 6).
Therefore 4 chars are used to rep...
How to randomly sort (scramble) an array in Ruby?
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293
Built in now:
[1,2,3,4].shuffle => [2, 1, 3, 4]
[1,2,3,4].shuffle => [1, 3, 2, 4]
...
How to get device make and model on iOS?
...elName)
The result should be:
// Output on a simulator
@"i386" on 32-bit Simulator
@"x86_64" on 64-bit Simulator
// Output on an iPhone
@"iPhone1,1" on iPhone
@"iPhone1,2" on iPhone 3G
@"iPhone2,1" on iPhone 3GS
@"iPhone3,1" on iPhone 4 (GSM)
@"iPhone3,2" on iPhone 4 (GSM Rev A)
@"iPhone...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...p.NaN], range(3), range(3)])
>>> df.isnull()
0 1 2
0 False False False
1 False True False
2 False False True
3 False False False
4 False False False
>>> df.isnull().any(axis=1)
0 False
1 True
2 True
3 False
4 False
dtype: bool
>...
How can I get a Bootstrap column to span multiple rows?
... <div class="col-md-6">
<div class="well">2</div>
</div>
<div class="col-md-6">
<div class="well">3</div>
</div>
</div>
<div class="row">
...
Multiple linear regression in Python
...ress my dependent variable (y) against several independent variables (x1, x2, x3, etc.).
13 Answers
...
Why does ~True result in -2?
...
240
int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 ...
Remove duplicated rows using dplyr
...tion for this purpose.
Original answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_num...
python numpy machine epsilon
...for a given float type is to use np.finfo():
print(np.finfo(float).eps)
# 2.22044604925e-16
print(np.finfo(np.float32).eps)
# 1.19209e-07
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Annotating text on individual facet in ggplot2
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edited Aug 9 '12 at 19:24
Andy
3,8192828 silver badges2626 bronze badges
answered Aug 9 '12 a...