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NSDictionary - Need to check whether dictionary contains key-value pair or not
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194
Just ask it for the objectForKey:@"b". If it returns nil, no object is set at that key.
if ([x...
Vim: How do you open another [No Name] buffer like the one on startup?
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324
There are many ways to open a new buffer with no name, the simplest of which is :new.
:new will...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... return x*2, x*3
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In [3]: df = DataFrame({'a': [1,2,3], 'b': [2,3,4]})
In [4]: df
Out[4]:
a b
0 1 2
1 2 3
2 3 4
In [5]: df["A1"], df["A2"] = zip(*df["a"].map(calculate))
In [6]: df
Out[6]:
a b A1 A2
0 1 2 2 3
1 2 3 4 6
2 3 4 6 9
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How to import existing *.sql files in PostgreSQL 8.4?
I am using PostgreSQL 8.4, and I have some *.sql files to import into a database. How can I do so?
5 Answers
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How to migrate back from initial migration in Django 1.7?
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supervacuo
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answered Sep 1 '14 at 14:25
ChillarAnandChillarAnand
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Routes with Dash `-` Instead of Underscore `_` in Ruby on Rails
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4 Answers
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Active
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What is the full path to the Packages folder for Sublime text 2 on Mac OS Lion
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Rob CowieRob Cowie
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Using HeapDumpOnOutOfMemoryError parameter for heap dump for JBoss
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awk without printing newline
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CodeRainCodeRain
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Add column to SQL Server
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answered Apr 14 '11 at 16:07
Martin SmithMartin Smith
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