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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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How do I connect to a MySQL Database in Python?
... rpm-based), or dnf install python-mysql (for modern fedora distro) in command line to download.)
For Mac, you can install MySQLdb using Macport.
2 - Usage
After installing, Reboot. This is not mandatory, But it will prevent me from answering 3 or 4 other questions in this post if something goes ...
Using ViewPagerIndicator library with Android Studio and Gradle
...cator library , but I'm unable to get it working with my Gradle project in Android Studio.
19 Answers
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How to open every file in a folder?
...have a python script parse.py, which in the script open a file, say file1, and then do something maybe print out the total number of characters.
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apc vs eaccelerator vs xcache
Im doing research on which one of these to use and I can't really find one that stands out. Eaccelerator is faster than APC , but APC is better maintained. Xcache is faster but the others have easier syntax.
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How do I use boolean variables in Perl?
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@BlueWaldo: you can also use cmp and <=> when comparing and assigning the results of the comparison to a scalar. $var = $var1 cmp $var2; 'cmp' and '<=>' (used for numeric comparisons) returns -1, 0, or 1 if left argument is less than, equal to,...
Which is more efficient: Multiple MySQL tables or one large table?
...inally it was set up in various tables meaning data is linked with UserIds and outputting via sometimes complicated calls to display and manipulate the data as required. Setting up a new system, it almost makes sense to combine all of these tables into one big table of related content.
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Is there a replacement for unistd.h for Windows (Visual C)?
...n't exist. Removing it, I get complaints about misssing prototypes for 'srandom', 'random', and 'getopt'.
I know I can replace the random functions, and I'm pretty sure I can find/hack-up a getopt implementation.
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Is it possible to read from a InputStream with a timeout?
...tream always returns 0.
This method should be overridden by subclasses.
And indeed, the concrete input stream classes do override available(), providing meaningful values, not constant 0s.
Second Caveat: Ensure you use carriage-return when typing input in Windows.
If using System.in, your progr...
Does bit-shift depend on endianness?
... equivalent of converting to big endian, the shifting operation comes next and then the new value is stored back in memory, which is where the little endian byte order comes into effect again.
Update, thanks to @jww: On PowerPC the vector shifts and rotates are endian sensitive. You can have a val...