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Dynamic array in C#
... use the ToArray() method after initiating your List dynamically
List<string> list = new List<string>();
list.Add("one");
list.Add("two");
list.Add("three");
string[] array = list.ToArray();
Of course, this has sense only if the size of the array is never known nor fixed ex-ante.
if...
TypeError: unhashable type: 'dict'
...e the keys have to be hashable. As a general rule, only immutable objects (strings, integers, floats, frozensets, tuples of immutables) are hashable (though exceptions are possible). So this does not work:
>>> dict_key = {"a": "b"}
>>> some_dict[dict_key] = True
Traceback (most re...
How to display unique records from a has_many through relationship?
...ct => "DISTINCT products.*). In the first case, ALL records are fetched and rails removes the duplicates for you. In the later case, only non-duplicate records are fetched from the db so it might offer better performance if you have a large result set.
– mbreining
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Fit Image in ImageButton in Android
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I want them to cover 75% of the button area.
Use android:padding="20dp" (adjust the padding as needed) to control how much the image takes up on the button.
but where as some images cover less area, some are too big to fit into the imageButton. How to programatically re...
Selecting a row of pandas series/dataframe by integer index
...operator, [] is to select columns.
When the indexing operator is passed a string or integer, it attempts to find a column with that particular name and return it as a Series.
So, in the question above: df[2] searches for a column name matching the integer value 2. This column does not exist and a ...
Prevent screen rotation on Android
...).getConfiguration().orientation;
@Override
protected void onPostExecute(String things) {
context.setRequestedOrientation(PlayListFragment.screenOrientation);
or
context.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_FULL_SENSOR);
}
The only drawback here is that it require...
How to compare variables to undefined, if I don’t know whether they exist? [duplicate]
...a valid variable, do something here.
}
Note that typeof always returns a string, and doesn't generate an error if the variable doesn't exist at all.
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align text center with android
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Set also android:gravity parameter in TextView to center.
For testing the effects of different layout parameters I recommend to use different background color for every element, so you can see how your layout changes with parameters ...
How to get the current date and time
...me fields and the DateFormat class should be used to format and parse date strings.
– Paolo M
Aug 7 '13 at 14:06
9
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How to calculate the SVG Path for an arc (of a circle)
...t (200,200), radius 25, how do I draw an arc from 270 degree to 135 degree and one that goes from 270 to 45 degree?
13 Answ...