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Pandas aggregate count distinct
...
How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
How to bind a List to a ComboBox?
...ry = (Country)comboBox1.SelectedItem;.
If you want the ComboBox to dynamically update you'll need to make sure that the data structure that you have set as the DataSource implements IBindingList; one such structure is BindingList<T>.
Tip: make sure that you are binding the DisplayMember to...
Setting dynamic scope variables in AngularJs - scope.
...one please add a new answer to the question!
Here is the example:
var the_string = 'life.meaning';
// Get the model
var model = $parse(the_string);
// Assigns a value to it
model.assign($scope, 42);
// Apply it to the scope
// $scope.$apply(); <- According to comments, this is no longer need...
How can I generate random alphanumeric strings?
...retty much linearly when generating longer strings (so long as there's actually enough memory available). Having said that, Dan Rigby's answer was almost twice as fast as this one in every test.
– LukeH
Aug 28 '09 at 0:33
...
Do Java arrays have a maximum size?
...ry easy to test.
In a recent HotSpot VM, the correct answer is Integer.MAX_VALUE - 5. Once you go beyond that:
public class Foo {
public static void main(String[] args) {
Object[] array = new Object[Integer.MAX_VALUE - 4];
}
}
You get:
Exception in thread "main" java.lang.OutOfMemoryEr...
How to add default value for html ? [closed]
...swered Jun 2 '14 at 16:54
bhavya_wbhavya_w
6,06455 gold badges2525 silver badges3636 bronze badges
...
How to split a large text file into smaller files with equal number of lines?
...a large (by number of lines) plain text file that I'd like to split into smaller files, also by number of lines. So if my file has around 2M lines, I'd like to split it up into 10 files that contain 200k lines, or 100 files that contain 20k lines (plus one file with the remainder; being evenly divi...
Concept of void pointer in C programming
...ligned at 4-byte boundary to be dereferenced).
For example, reading uint16_t from void*:
/* may receive wrong value if ptr is not 2-byte aligned */
uint16_t value = *(uint16_t*)ptr;
/* portable way of reading a little-endian value */
uint16_t value = *(uint8_t*)ptr
| ((*((uint8_t*)...
Twitter Bootstrap: div in container with 100% height
...
The #map is actually obscured behind the navbar in this example.
– Ethereal
May 7 '13 at 19:57
|...
Does R have an assert statement as in python?
...ndition that will throw an error in your program. Here's an example:
Less_Than_8 = function(x) return(x < 8)
for (i in 1:10)
{
print(i)
stopifnot(Less_Than_8(i))
}
This will print the numbers 1 through 8, then print a message that says
Error: Less_Than_8(i) is not TRUE
It would be ni...