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Closure in Java 7 [closed]
...e pioneers introducing closures in Java. His post on closures from January 28, 2007 is named A Definition of Closures On his blog there is lots of information to get you started as well as videos. An here is an excellent Google talk - Advanced Topics In Programming Languages - Closures For Java with...
Python argparse: default value or specified value
...
286
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--example', nargs='?',...
Numpy how to iterate over columns of array?
...
228
Just iterate over the transposed of your array:
for column in array.T:
some_function(colum...
How do I use the includes method in lodash to check if an object is in the collection?
...
226
The includes (formerly called contains and include) method compares objects by reference (or m...
Overload constructor for Scala's Case Classes?
In Scala 2.8 is there a way to overload constructors of a case class?
2 Answers
2
...
What is the difference between Ruby 1.8 and Ruby 1.9
..."cat"[1]
=> 97
{"a","b"} No Longer Supported
Ruby 1.9
irb(main):002:0> {1,2}
SyntaxError: (irb):2: syntax error, unexpected ',', expecting tASSOC
Ruby 1.8.6
irb(main):001:0> {1,2}
=> {1=>2}
Action: Convert to {1 => 2}
Array.to_s Now Contains Punctuation
Ruby 1.9
irb...
Checking for the correct number of arguments
...
218
#!/bin/sh
if [ "$#" -ne 1 ] || ! [ -d "$1" ]; then
echo "Usage: $0 DIRECTORY" >&2
e...
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...
List comprehension rebinds names even after scope of comprehension. Is this right?
...
172
List comprehensions leak the loop control variable in Python 2 but not in Python 3. Here's Guid...
How can I make pandas dataframe column headers all lowercase?
...e(3,0,-1), 'C':list('abc')})
>>> data
A B C
0 0 3 a
1 1 2 b
2 2 1 c
>>> data.columns = map(str.lower, data.columns)
>>> data
a b c
0 0 3 a
1 1 2 b
2 2 1 c
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