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How to add an empty column to a dataframe?
What's the easiest way to add an empty column to a pandas DataFrame object? The best I've stumbled upon is something like
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Convert int to char in java
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My answer is similar to jh314's answer but I'll explain a little deeper.
What you should do in this case is:
int a = 1;
char b = (char)(a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
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MySQL error: key specification without a key length
...you say "MySQL can index only the first N chars of a BLOB or TEXT column", what is the value of N?
– jameshfisher
Apr 23 '14 at 9:10
2
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d3 axis labeling
...f you're positioning with "x" and "y", you need to swap the positions from what I expected.
– lubar
May 29 '13 at 16:33
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When is JavaScript's eval() not evil?
...king command". So, when is it OK to use something dangerous? When you know what the danger is, and when you're taking the appropriate precautions.
To the point, let's look at the dangers in the use of eval(). There are probably many small hidden dangers just like everything else, but the two big ri...
Why does std::getline() skip input after a formatted extraction?
... function. And all unformatted input functions have the following code somewhat in common:
typename std::basic_istream<charT>::sentry ok(istream_object, true);
The above is a sentry object which is instantiated in all formatted/unformatted I/O functions in a standard C++ implementation. Sentr...
Get file name from URI string in C#
I have this method for grabbing the file name from a string URI. What can I do to make it more robust?
8 Answers
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Error: allowDefinition='MachineToApplication' beyond application level
...ease didn't work but cleaning in Debug did. (Probably a combo of the 2 was what was needed, i.e. clear out any old refs to dlls, whether Debug or Release).
– Scotty.NET
Jul 19 '13 at 14:34
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How to split data into training/testing sets using sample function
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I'm a little confused what guarantees this code returns a unique test and train df? It seems to work, don't get me wrong. Just having trouble understanding how subtracting the indices leads to unique observations. For instance, if you had a df wit...
Concatenating null strings in Java [duplicate]
...ng like a "meta"-behaviour, for example when debugging, when I want to see what's inside that variable, but the default "non-meta" behaviour should be throwing an NPE.
– aliopi
Jul 21 '17 at 10:13
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