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Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?
... On all modern implementations, anything beyond int pow(int base, unsigned char exponent) is somewhat useless anyway. Either the base is 0, or 1, and the exponent doesn't matter, it's -1, in which case only the last bit of exponent matters, or base >1 || base< -1 in which case exponent<256 ...
What is a NullReferenceException, and how do I fix it?
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every found location and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine whether you exp...
Difference between ActionBarSherlock and ActionBar Compatibility
...ar (CAB) a menu that takes over the action bar, used for example for multi select (http://developer.android.com/design/patterns/new-4-0.html) This is a ICS feature (!) For this, an implementation of the ActionMode class (introduced in API level 11) had to be introduced into the ActionbarSherlock lib...
XAMPP, Apache - Error: Apache shutdown unexpectedly
...- From the XAMPP Control Panel, under Apache, click the Config button, and select the Apache (httpd.conf).
Inside the httpd.conf file, somehow I found a line that says:
Listen 80
And change the 80 into any number / port you want. In my scenario I’m using port 8080.
Listen 8080
Still from th...
Delete column from pandas DataFrame
...the original
data can be modified without creating a copy.
Popped
Column selection, addition, deletion
Delete column column-name:
df.pop('column-name')
Examples:
df = DataFrame.from_items([('A', [1, 2, 3]), ('B', [4, 5, 6]), ('C', [7,8, 9])], orient='index', columns=['one', 'two', 'three'])
...
Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
ReactJS render string with non-breaking spaces
I have some props that has a string that could contain characters such as &.
It also contains spaces. I want to replace all spaces with &nbsp; .
...
Is there an IDictionary implementation that, on missing key, returns the default value instead of th
...<K, V>(this IDictionary<K, V> dict, K key, Func<V> defValSelector)
{
V value;
return dict.TryGetValue(key, out value) ? value : defValSelector();
}
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How to read contacts on Android 2.0
...,
ContactsContract.Contacts.HAS_PHONE_NUMBER,
};
String SELECTION = ContactsContract.Contacts.HAS_PHONE_NUMBER + "='1'";
Cursor contacts = managedQuery(contactUri, PROJECTION, SELECTION, null, null );
The above chunk of code returns a Cursor that points to the resulting query t...
In Python, how do I split a string and keep the separators?
...re.sub. I wanted to split on a ending percent so I just subbed in a double character and then split, hacky but worked for my case: re.split('% ', re.sub('% ', '%% ', '5.000% Additional Whatnot')) --> ['5.000%', 'Additional Whatnot']
– Kyle James Walker
Oct 1...