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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...
No secret option provided to Rack::Session::Cookie warning?
I am running Rails 3.2.3, Ruby 1.9 under Fedora 17. I get this warning, when I run rails s , and how do I fix?
7 Answers
...
Logical operators for boolean indexing in Pandas
...
219
When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x...
How do I forward parameters to other command in bash script?
...
245
Use the shift built-in command to "eat" the arguments. Then call the child process and pass it...
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 ...
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
>...
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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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
...
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...