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How do I retrieve the number of columns in a Pandas data frame?
How do you programmatically retrieve the number of columns in a pandas dataframe? I was hoping for something like:
6 Answer...
How do I determine the target architecture of static library (.a) on Mac OS X?
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Another option is lipo; its output is brief and more readable than otool's.
An example:
% lipo -info /usr/lib/libiodbc.a
Architectures in the fat file: /usr/lib/libiodbc.a are: x86_64 i386 ppc
% lipo -info libnonfatarchive.a
input file libnonfatarchive.a is not a fa...
Do I need to close() both FileReader and BufferedReader?
...Reader.close()
closes the stream according to javadoc for BufferedReader and InputStreamReader
as well as
FileReader.close()
does.
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How to set the maximum memory usage for JVM?
...y> -Xmx<memory>. Use M or G after the numbers for indicating Megs and Gigs of bytes respectively. -Xms indicates the minimum and -Xmx the maximum.
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How can I verify if one list is a subset of another?
...answer to your question, however.
A list may contain items multiple times and has a specific order. A set does not. Additionally, sets only work on hashable objects.
Are you asking about subset or subsequence (which means you'll want a string search algorithm)? Will either of the lists be the sam...
MySQL: Transactions vs Locking Tables
... confused with transactions vs locking tables to ensure database integrity and make sure a SELECT and UPDATE remain in sync and no other connection interferes with it. I need to:
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C# DLL config file
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It is not trivial to create a .NET configuration file for a .DLL, and for good reason. The .NET configuration mechanism has a lot of features built into it to facilitate easy upgrading/updating of the app, and to protect installed apps from trampling each others configuration files.
There...
Unique constraint on multiple columns
...o I add a unique constraint for columns fcode, scode, dcode with t-sql and/or management studio ? fcode, scode, dcode must be unique together.
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difference between use and require
Can anyone explain the difference between use and require , both when used directly and as :use and :require in the ns macro?
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Django datetime issues (default=datetime.now())
...it looks like datetime.now() is being evaluated when the model is defined, and not each time you add a record.
Django has a feature to accomplish what you are trying to do already:
date = models.DateTimeField(auto_now_add=True, blank=True)
or
date = models.DateTimeField(default=datetime.now, bl...