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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...
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...
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...
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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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 ...
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 ...
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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convert a JavaScript string variable to decimal/money
...ent.getElementById(amtid4).innerHTML);
For formatting numbers, use toFim>x m>ed:
var num = parseFloat(document.getElementById(amtid4).innerHTML).toFim>x m>ed(2);
num is now a string with the number formatted with two decimal places.
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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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