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how to use sed, awk, or gawk to print only what is matched?
... tried * instead and I added p tag for printing match:
sed -n 's/^.*abc\([0-9]*\)xyz.*$/\1/p' example.txt
For matching at least one numeric character without +, I would use:
sed -n 's/^.*abc\([0-9][0-9]*\)xyz.*$/\1/p' example.txt
...
leading zeros in rails
...eld, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
...
Specify pane percentage in tmuxinator project
...r use with select-layout. For example:
$ tmux list-windows
0: ksh [159x48]
layout: bb62,159x48,0,0{79x48,0,0,79x48,80,0}
$ tmux select-layout bb62,159x48,0,0{79x48,0,0,79x48,80,0}
tmux automatically adjusts the size of the layout for the current window
size. Not...
Twitter's typeahead.js suggestions are not styled (have no border, transparent background, etc.)
I'm using twitter's typeahead.js 0.9.3 and it seems my suggestions are not styled at all.
9 Answers
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Remove duplicated rows using dplyr
...r 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_number(z) == 1)
## Source: local data fr...
Make xargs execute the command once for each line of input
...
405
The following will only work if you do not have spaces in your input:
xargs -L 1
xargs --max-l...
Replacing NAs with latest non-NA value
...
divibisan
7,90699 gold badges2626 silver badges4343 bronze badges
answered Oct 12 '11 at 5:32
Dirk EddelbuettelDir...
Is it possible to declare two variables of different types in a for loop?
...tax has been supported in gcc and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set...
How to create an array containing 1…N
...
409
If I get what you are after, you want an array of numbers 1..n that you can later loop through....
How do you create a yes/no boolean field in SQL server?
...
The equivalent is a BIT field.
In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions).
When accessing the database through ASP.NET it will expose the field as a b...