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pandas three-way joining multiple dataframes on columns
...SV files. Each has the first column as the (string) names of people, while all the other columns in each dataframe are attributes of that person.
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How can I create an error 404 in PHP?
My .htaccess redirects all requests to /word_here to /page.php?name=word_here . The PHP script then checks if the requested page is in its array of pages.
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Visual Studio support for new C / C++ standards?
I keep reading about C99 and C++11 and all these totally sweet things that are getting added to the language standard that might be nice to use someday. However, we currently languish in the land of writing C++ in Visual Studio.
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Received an invalid column length from the bcp client for colid 6
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Specifically, if you have any columns that are VARCHAR smaller than 4, watch out for NULL in your data getting misinterpreted as the 4char string "NULL"
– CrazyPyro
Feb 11 at 8:13
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How to post data to specific URL using WebClient in C#
...s the garbage collector will clean up unmanaged resources and the like by calling the destructor (e.g., WebClient inherits from Component, which contains ~Component() {Dispose(false);}). The problem is that the garbage collector may take an arbitrarily long time to do so, since it does not account ...
efficient circular buffer?
...1] #[10, 11, 3, 8] 3, 11
Class:
class circularlist(object):
def __init__(self, size, data = []):
"""Initialization"""
self.index = 0
self.size = size
self._data = list(data)[-size:]
def append(self, value):
"""Append an element"""
if le...
Best way to assert for numpy.array equality?
..._equal is more reliable.
update
A few versions ago numpy obtained assert_allclose which is now my favorite since it allows us to specify both absolute and relative error and doesn't require decimal rounding as the closeness criterion.
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Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?
... of power functions (and others). C++11 [c.math] /11 states, after listing all the float/double/long double overloads (my emphasis, and paraphrased):
Moreover, there shall be additional overloads sufficient to ensure that, if any argument corresponding to a double parameter has type double or an...
What is the difference between user and kernel modes in operating systems?
... CPU instruction and
reference any memory address. Kernel
mode is generally reserved for the
lowest-level, most trusted functions
of the operating system. Crashes in
kernel mode are catastrophic; they
will halt the entire PC.
User Mode
In User mode, the executing code has no abili...
Python “raise from” usage
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The difference is that when you use from, the __cause__ attribute is set and the message states that the exception was directly caused by. If you omit the from then no __cause__ is set, but the __context__ attribute may be set as well, and the traceback then shows the co...