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Get the first item from an iterable that matches a condition
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13 Answers
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Checking if array is multidimensional or not?
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136
The short answer is no you can't do it without at least looping implicitly if the 'second dimen...
How do I use raw_input in Python 3
I am using Python 3.1 and can't get the raw_input to "freeze" the dos pop-up. The book I'm reading is for Python 2.5 and I'm using Python 3.1
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How to extract one column of a csv file
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137
You could use awk for this. Change '$2' to the nth column you want.
awk -F "\"*,\"*" '{print $...
Why is rbindlist “better” than rbind?
...d will join by position
eg
do.call(rbind, list(data.frame(a = 1:2, b = 2:3), data.frame(b = 1:2, a = 2:3)))
## a b
## 1 1 2
## 2 2 3
## 3 2 1
## 4 3 2
rbindlist(list(data.frame(a = 1:5, b = 2:6), data.frame(b = 1:5, a = 2:6)))
## a b
## 1: 1 2
## 2: 2 3
## 3: 1 2
## 4: 2 3
Some...
Build an ASCII chart of the most commonly used words in a given text [closed]
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123
votes
LabVIEW 51 nodes, 5 structures, 10 diagrams
Teaching the elephant to tap-dan...
Paste multiple columns together
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# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three columns collapsed together
data$x <- apply( d...
How to convert hex to rgb using Java?
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return new Color(
Integer.valueOf( colorStr.substring( 1, 3 ), 16 ),
Integer.valueOf( colorStr.substring( 3, 5 ), 16 ),
Integer.valueOf( colorStr.substring( 5, 7 ), 16 ) );
}
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Concatenate a vector of strings/character
...ta, collapse = '')
Thanks to http://twitter.com/onelinetips/status/7491806343
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
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359
SQLiteOpenHelper onCreate() and onUpgrade() callbacks are invoked when the database is actuall...