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What is `git diff --patience` for?
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edited Jun 20 at 9:12
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answered Oct 28 '10 at 16:34
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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
Extract a regular expression match
...nd adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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find vs find_by vs where
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104
Use whichever one you feel suits your needs best.
The find method is usually used to retrieve ...
Merge Images Side by Side(Horizontally)
I have five images of sizes: 600x30, 600x30, 600x30, 600x30, 810x30. Their names are: 0.png, 1.png, 2.png, 3.png, 4.png, respectively.
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Rails detect if request was AJAX
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edited Jul 10 '15 at 16:46
answered Nov 22 '11 at 1:08
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Format date and time in a Windows batch script
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150
I ended up with this script:
set hour=%time:~0,2%
if "%hour:~0,1%" == " " set hour=0%hour:~1,1%...
How to get current time in milliseconds in PHP?
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The short answer is:
$milliseconds = round(microtime(true) * 1000);
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How do you read CSS rule values with JavaScript?
...(className) {
var cssText = "";
var classes = document.styleSheets[0].rules || document.styleSheets[0].cssRules;
for (var x = 0; x < classes.length; x++) {
if (classes[x].selectorText == className) {
cssText += classes[x].cssText || classes[x].style.cssText...
C# Double - ToString() formatting with two decimal places but no rounding
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210
I use the following:
double x = Math.Truncate(myDoubleValue * 100) / 100;
For instance:
If t...