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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
...
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...
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".
...
Perl build, unit testing, code coverage: A complete working example
...
105
It took me a while and it also took me taking small snippets from a number of different sources...
How to configure PostgreSQL to accept all incoming connections
...
Just use 0.0.0.0/0.
host all all 0.0.0.0/0 md5
Make sure the listen_addresses in postgresql.conf (or ALTER SYSTEM SET) allows incoming connections on all available IP interfaces.
listen_addres...
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...
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...
C++: Rounding up to the nearest multiple of a number
...ger math.
int roundUp(int numToRound, int multiple)
{
if (multiple == 0)
return numToRound;
int remainder = numToRound % multiple;
if (remainder == 0)
return numToRound;
return numToRound + multiple - remainder;
}
Edit: Here's a version that works with negative n...
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...
How to change border color of textarea on :focus
... {
outline: none !important;
border:1px solid red;
box-shadow: 0 0 10px #719ECE;
}
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