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pandas: How do I split text in a column into multiple rows?
I'm working with a large csv file and the next to last column has a string of text that I want to split by a specific delimiter. I was wondering if there is a simple way to do this using pandas or python?
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$PHP_AUTOCONF errors on mac os x 10.7.3 when trying to install pecl extensions
...tp and memcache and in both cases, I get similar errors. This is on MAC OS X 10.7.3 (lion) and I also have XCODE installed on it. I also installed Zend Server community edition before running these commands and have CFLAGS='-arch i386 -arch x86_64' environment variables set. So please help with what...
How to remove item from list in C#?
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List<T> has two methods you can use.
RemoveAt(int index) can be used if you know the index of the item. For example:
resultlist.RemoveAt(1);
Or you can use Remove(T item):
var itemToRemove = resultlist.Single(r => r.Id == 2);
resultList.Remove(itemToRemove);
When you ar...
Opposite of %in%: exclude rows with values specified in a vector
...presented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
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Java Name Hiding: The Hard Way
I have a problem with name hiding that is extremely hard to solve. Here is a simplified version that explains the problem:
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Is Ruby pass by reference or by value?
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Ruby is pass-by-value. No ifs. No buts. No exceptions. If you want to know whether Ruby (or any other language) is pass-by-reference or pass-by-value, just try it out: def foo(bar) bar = 'reference' end; baz = 'value'; foo(baz); puts "Ruby is pass-by-#{baz}".
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“Variable” variables in Javascript?
I know it's possible in PHP to have "variable" variables. For example
7 Answers
7
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What exactly does an #if 0 … #endif block do?
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Not only does it not get executed, it doesn't even get compiled.
#if is a preprocessor command, which gets evaluated before the actual compilation step. The code inside that block doesn't appear in the compiled binary.
It's often used for temporaril...
Does Haskell require a garbage collector?
...grams, the lifetime of an object can only be determined at runtime.
For example, consider the following program:
main = loop (Just [1..1000]) where
loop :: Maybe [Int] -> IO ()
loop obj = do
print obj
resp <- getLine
if resp == "clear"
then loop Nothing
else loop o...
How to invoke the super constructor in Python?
...structor is invoked implicitly. How does one invoke it in Python? I would expect super(self) but this doesn't work.
7 Ans...