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Python Pandas merge only certain columns
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You can use .loc to select the specific columns with all rows and then pull that. An example is below:
pandas.merge(dataframe1, dataframe2.iloc[:, [0:5]], how='left', on='key')
In this example, you are merging dataframe1 and dataframe2. You have chosen to do an outer left jo...
Why does Python code use len() function instead of a length method?
...on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in iter() function (or have the method called behind the scenes for you) on objects which are iterable.
See Emulating container types for m...
How do I call setattr() on the current module?
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import sys
thismodule = sys.modules[__name__]
setattr(thismodule, name, value)
or, without using setattr (which breaks the letter of the question but satisfies the same practical purposes;-):
globals()[name] = value
Note: at module scope, the latter is eq...
How can I use threading in Python?
...ticle/blog post that you should definitely check out (no affiliation) - Parallelism in one line: A Better Model for Day to Day Threading Tasks. I'll summarize below - it ends up being just a few lines of code:
from multiprocessing.dummy import Pool as ThreadPool
pool = ThreadPool(4)
results = pool.m...
Rounding up to next power of 2
...mon: it's the portable solution. There's no common efficient algorithm for all architectures
– phuclv
Dec 6 '13 at 9:27
5
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Turn a simple socket into an SSL socket
...()
{
SSL_load_error_strings();
SSL_library_init();
OpenSSL_add_all_algorithms();
}
void DestroySSL()
{
ERR_free_strings();
EVP_cleanup();
}
void ShutdownSSL()
{
SSL_shutdown(cSSL);
SSL_free(cSSL);
}
Now for the bulk of the functionality. You may want to add a while lo...
How to get the current directory in a C program?
...been looking at opendir() and telldir() , but telldir() returns a off_t (long int) , so it really doesn't help me.
6...
Getting number of elements in an iterator in Python
...ve an answer, this answer avoids instantiation of a list, and it is empirically faster by a constant than the reduce method listed above.
– Phillip Nordwall
Aug 2 '12 at 15:27
5
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Integrating MySQL with Python in Windows
...rrently, I would recommend using PyMySQL. It's pure python, so it supports all OSes equally, it's almost a drop-in replacement for mysqldb, and it also works with python 3. The best way to install it is using pip. You can install it from here (more instructions here), and then run:
pip install pymy...
How do I install cygwin components from the command line?
... the Cygwin package similar to apt-get on Debian or yum on redhat that allows me to install components from the command line?
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