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How do I replace NA values with zeros in an R dataframe?
...u post it and not worked. Because this I posted the question. But I tried know and worked perfectly. I think I was doing something wrong.
– Renato Dinhani
Nov 17 '11 at 14:08
12
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Is it a good practice to use try-except-else in Python?
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"I do not know if it is out of ignorance, but I do not like that
kind of programming, as it is using exceptions to perform flow control."
In the Python world, using exceptions for flow control is common and normal.
Even the Python ...
ViewPager and fragments — what's the right way to store fragment's state?
... separation of UI logic into some modules. But along with ViewPager its lifecycle is still misty to me. So Guru thoughts are badly needed!
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How can I load storyboard programmatically from class?
... storyboard programmatically. Project was started developing with xib, and now it's very hard to nest all xib files in storyboard. So I was looking a way to do it in code, like with alloc, init, push for viewControllers. In my case I have only one controller in storyboard: UITableViewController ,...
Which SQL query is faster? Filter on Join criteria or Where clause?
...same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = a.ID
AND a.ID = 1
LEFT JOIN
TableB b
ON ...
Reading InputStream as UTF-8
...a text/plain file over the internet, line-by-line. The code I have right now is:
3 Answers
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Export specific rows from a PostgreSQL table as INSERT SQL script
... tool, it's just that it has error in date-time data in the script result. If none can give GUI tool solution in 2 days, your answer will be accepted
– null
Oct 10 '12 at 9:54
2
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How to list all properties of a PowerShell object
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If you want to know what properties (and methods) there are:
Get-WmiObject -Class "Win32_computersystem" | Get-Member
share
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Visual Studio can't build due to rc.exe
...this:
Microsoft left a few things out of their MSVT package. Since no one knows whether they were left out by mistake or for license reasons, no one with MSVC is too interested in giving them out. A few Google searches turn up some tricky sources. Fortunately, Microsoft has finally wised up and solv...
Python Dictionary Comprehension
...n't use them to add keys to an existing dictionary. Also, you have to specify the keys and values, although of course you can specify a dummy value if you like.
>>> d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
...