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What's the point of g++ -Wreorder?
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260
Consider:
struct A {
int i;
int j;
A() : j(0), i(j) { }
};
Now i is initialized t...
Add UIPickerView & a Button in Action sheet - How?
...ableViewController *)[[navigationController viewControllers] objectAtIndex:0];
tableViewController.tableData = self.statesArray;
tableViewController.navigationItem.title = @"States";
tableViewController.delegate = self;
[self presentViewController:navigationController animated:YES completion:nil];
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How do I properly compare strings in C?
...ngs using != or ==, you need to use strcmp:
while (strcmp(check,input) != 0)
The reason for this is because != and == will only compare the base addresses of those strings. Not the contents of the strings themselves.
shar...
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...
Javascript add leading zeroes to date
I've created this script to calculate the date for 10 days in advance in the format of dd/mm/yyyy:
24 Answers
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Why is setTimeout(fn, 0) sometimes useful?
...locks the updating of the DOM.
Your workaround was:
setTimeout(callback, 0)
Invoking setTimeout with a callback, and zero as the second argument will schedule the callback to be run asynchronously, after the shortest possible delay - which will be around 10ms when the tab has focus and the JavaS...
How to add item to the beginning of List?
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Use the Insert method:
ti.Insert(0, initialItem);
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What is the best way to count “find” results?
...ntf '.' \; | wc -c , but this takes far too long when there are more than 10000 results. Is there no faster/better way to do this?
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How do I compare version numbers in Python?
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10 Answers
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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 ...