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What is the use of the ArraySegment class?
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edited Oct 1 '19 at 22:03
answered Oct 26 '11 at 18:15
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Select first 4 rows of a data.frame in R
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156
Use head:
dnow <- data.frame(x=rnorm(100), y=runif(100))
head(dnow,4) ## default is 6
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What is a “callback” in C and how are they implemented?
...RandomValue(void)
{
return rand();
}
int main(void)
{
int myarray[10];
populate_array(myarray, 10, getNextRandomValue);
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}
Here, the populate_array function takes a function pointer as its third parameter, and calls it to get the values to populate the array with. We've written...
Bower and devDependencies vs dependencies
I ran 'yo angular' and realized afterwards that it installs 1.0.8, I uninstalled the angular components, however the original bower.json file had angular-mocks and angular-scenario under 'devDependencies' when I re-add all the 1.2.0-rc.2 components angular-mocks and angular-scenario under dependenci...
Reload django object from database
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As of Django 1.8 refreshing objects is built in. Link to docs.
def test_update_result(self):
obj = MyModel.objects.create(val=1)
MyModel.objects.filter(pk=obj.pk).update(val=F('val') + 1)
# At this point obj.val is still 1, b...
ERROR: Error installing capybara-webkit:
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218
If you are in Ubuntu do
sudo apt-get install qt4-dev-tools libqt4-dev libqt4-core libqt4-gui
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std::function and std::bind: what are they, and when should they be used?
...ithms, but I haven't understood what Stroustrup says about them in the C++11 FAQ .
4 Answers
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How to delete and replace last line in the terminal using bash?
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117
echo a carriage return with \r
seq 1 1000000 | while read i; do echo -en "\r$i"; done
from ...
setup cron tab to specific time of during weekdays
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177
Same as you did for hours:
*/2 09-18 * * 1-5 /path_to_script
0 and 7 stand for Sunday
6 sta...
UICollectionView Set number of columns
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17 Answers
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