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How to reorder data.table columns (without copying)
... 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all set* functions change their input by reference. That is, no copy is made at all, other than temporary working memory, which is as large as one column.
so should be pretty efficient. See ?setcolorder for details.
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Automatic popping up keyboard on start Activity
...ity with a lot of EditText's in them. When I open the activity it automatically focusses to the first EditText and displays the virtual keyboard.
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Putting a simple if-then-else statement on one line [duplicate]
I'm just getting into Python and I really like the terseness of the syntax. However, is there an easier way of writing an if - then - else statement so it fits on one line?
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Get table names using SELECT statement in MySQL
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To get the name of all tables use:
SELECT table_name FROM information_schema.tables;
To get the name of the tables from a specific database use:
SELECT table_name FROM information_schema.tables
WHERE table_schema = 'your_database_name';
N...
SVN how to resolve new tree conflicts when file is added on two branches
...ing add upon merge' variety. Fixed expectations in r35341.
(This is also called "evil twins" in ClearCase by the way):
a file is created twice (here "added" twice) in two different branches, creating two different histories for two different elements, but with the same name.
The theoretical solutio...
Does Internet Explorer 8 support HTML 5?
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so the answer is that for all fits and purposes, IE8 does not support html5 - just some randome bits and pieces of it. Which makes using HTML5 (as in HTML markup, not scripting API's) moot.
– Roland Tepp
Sep 7 '...
Memory management in Qt?
... need to delete and/or destroy my objects? Is any of this handled automatically?
4 Answers
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Append lines to a file using a StreamWriter
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I assume you are executing all of the above code each time you write something to the file. Each time the stream for the file is opened, its seek pointer is positioned at the beginning so all writes end up overwriting what was there before.
You can so...
How to get value from form field in django framework?
...equest.POST) # A form bound to the POST data
if form.is_valid(): # All validation rules pass
# Process the data in form.cleaned_data
# ...
print form.cleaned_data['my_form_field_name']
return HttpResponseRedirect('/thanks/') # Redirect after ...
Block comments in html.erb templates in rails
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=begin I think the begin - end would be all =end # You may ignore my comment as its entirely commented :P
– Garfield
Jun 27 '10 at 17:45
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