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Apply function to all elements of collection through LINQ [duplicate]
...answered May 31 '14 at 4:47
Jack_2060Jack_2060
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When do you use the “this” keyword? [closed]
... is no reason to use it otherwise because being able to resolve a variable based on the scope chain should be clear enough that qualifying variables with it should be unnecessary.
EDIT: The C# documentation on "this" indicates one more use, besides the two I mentioned, for the "this" keyword - for ...
Get names of all keys in the collection
...You could do this with MapReduce:
mr = db.runCommand({
"mapreduce" : "my_collection",
"map" : function() {
for (var key in this) { emit(key, null); }
},
"reduce" : function(key, stuff) { return null; },
"out": "my_collection" + "_keys"
})
Then run distinct on the resulting collecti...
How to send an email with Gmail as provider using Python?
... line and use CRLF as EOL markers.
E.g.
msg = "\r\n".join([
"From: user_me@gmail.com",
"To: user_you@gmail.com",
"Subject: Just a message",
"",
"Why, oh why"
])
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C# Interfaces. Implicit implementation versus Explicit implementation
...entation" (Design Principles from Design Patterns).
For example, in an MVP-based web application:
public interface INavigator {
void Redirect(string url);
}
public sealed class StandardNavigator : INavigator {
void INavigator.Redirect(string url) {
Response.Redirect(url);
}
}
N...
How to change MenuItem icon in ActionBar programmatically
...m = menu.findItem(R.id.action_settings);
// set your desired icon here based on a flag if you like
settingsItem.setIcon(ContextCompat.getDrawable(this, R.drawable.ic_launcher));
return super.onPrepareOptionsMenu(menu);
}
...
Writing a Python list of lists to a csv file
...s pd
In [2]: a = [[1.2,'abc',3],[1.2,'werew',4],[1.4,'qew',2]]
In [3]: my_df = pd.DataFrame(a)
In [4]: my_df.to_csv('my_csv.csv', index=False, header=False)
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What does FETCH_HEAD in Git mean?
...
FETCH_HEAD is a short-lived ref, to keep track of what has just been fetched from the remote repository. git pull first invokes git fetch, in normal cases fetching a branch from the remote; FETCH_HEAD points to the tip of this bra...
How to specify the default error page in web.xml?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How to round a number to significant figures in Python
...t digit:
>>> from math import log10, floor
>>> def round_to_1(x):
... return round(x, -int(floor(log10(abs(x)))))
...
>>> round_to_1(0.0232)
0.02
>>> round_to_1(1234243)
1000000.0
>>> round_to_1(13)
10.0
>>> round_to_1(4)
4.0
>>> rou...