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How can I obtain the element-wise logical NOT of a pandas Series?
...n error, instead you'll get a garbage mask of ints that won't work as you em>x m>pect.
In[1]: df = pd.DataFrame({'A':[True, False, np.nan], 'B':[True, False, True]})
In[2]: df.dropna(inplace=True)
In[3]: df['A']
Out[3]:
0 True
1 False
Name: A, dtype object
In[4]: ~df['A']
Out[4]:
0 -2
0 -1
Name...
If vs. Switch Speed
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The compiler can build jump tables where applicable. For em>x m>ample, when you use the reflector to look at the code produced, you will see that for huge switches on strings, the compiler will actually generate code that uses a hash table to dispatch these. The hash table uses the strin...
Check if two linked lists merge. If so, where?
...e but in the end they should be restored", and
we could iterate the lists em>x m>actly twice
the following algorithm would be the solution.
First, the numbers. Assume the first list is of length a+c and the second one is of length b+c, where c is the length of their common "tail" (after the mergepoin...
JSON.parse vs. eval()
...n.parse just parses JSON whereas eval would leave the door open to all JS em>x m>pressions.
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Use curly braces to initialize a Set in Python
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There are two obvious issues with the set literal syntam>x m>:
my_set = {'foo', 'bar', 'baz'}
It's not available before Python 2.7
There's no way to em>x m>press an empty set using that syntam>x m> (using {} creates an empty dict)
Those may or may not be important to you.
The section of ...
How to truncate string using SQL server
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If col is em>x m>actly 15 in length it will get the entire string when doing left(col,15) and then put '...' on the end. Surely a better solution is checking 'when len(col) > 15'.
– Murphybro2
Dec 6 ...
Is pass-by-value a reasonable default in C++11?
...otential) move from prvalue
foo(std::move(lval)); // (potential) move from m>x m>value
and only minimal work is done. You'd need two overloads to do the same with references, void foo(T const&); and void foo(T&&);.
With that in mind, I now wrote my valued constructors as such:
class T {
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How do I save and restore multiple variables in python?
...be used with Python 3, as its default protocol produces binary (i.e. non-tem>x m>t) data (writing mode 'wb' and reading mode 'rb').
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Remove a character from the end of a variable
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And it is POSIm>X m>, so is pretty much portable.
– go2null
Nov 9 '15 at 4:13
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Updating and committing only a file's permissions using git version control
Just turned an some.sh file into an em>x m>ecutable ( chmod 755 ... ), the permissions were updated but not the content. Is there a way to commit the file into git, so that the em>x m>ecutable bit will be restored/set on clone / checkout / pull ?
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