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Why does Math.floor return a double?
...l to the argument and is equal to a mathematical integer". Given a value x > 2^53 that will not be the same as the value with its fractional part truncated. It may well be quite a bit smaller than that.
– Jim Garrison
Sep 5 '16 at 20:10
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Overloading Macro on Number of Arguments
...OO2)(__VA_ARGS__)
So if you have these macros:
FOO(World, !) # expands to FOO2(World, !)
FOO(foo,bar,baz) # expands to FOO3(foo,bar,baz)
If you want a fourth one:
#define GET_MACRO(_1,_2,_3,_4,NAME,...) NAME
#define FOO(...) GET_MACRO(__VA_ARGS__, FOO4, FOO3, FOO2)(__VA_ARGS__)
F...
JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
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Why wasn't PyPy included in standard Python?
...true of all "pure GC" strategies.
PyPy does not yet fully support Python 3.x, although that is an active work item.
PyPy is a great project, but runtime speed on CPU-intensive tasks isn't everything, and in many applications it's the least of many concerns. For instance, Django can run on PyPy an...
The static keyword and its various uses in C++
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Variables:
static variables exist for the "lifetime" of the translation unit that it's defined in, and:
If it's in a namespace scope (i.e. outside of functions and classes), then it can't be accessed from any other translation unit. This is known as "i...
How do I sort an observable collection?
...g an observable and returning the same object sorted can be done using an extension method. For larger collections watch out for the number of collection changed notifications.
I have updated my code to improve performance (thanks to nawfal) and to handle duplicates which no other answers here do at...
How to display full (non-truncated) dataframe information in html when converting from pandas datafr
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Set the display.max_colwidth option to -1:
pd.set_option('display.max_colwidth', -1)
set_option docs
For example, in iPython, we see that the information is truncated to 50 characters. Anything in excess is ellipsized:
If you set the display...
Regular expressions in an Objective-C Cocoa application
Initial Googling indicates that there's no built-in way to do regular expressions in an Objective-C Cocoa application.
10 A...
How many parameters are too many? [closed]
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How can I convert a string to a number in Perl?
...t and I need to convert that string into a floating point variable. So an example of the string I have is "5.45" and I want a floating point equivalent so I can add .1 to it. I have searched around the internet, but I only see how to convert a string to an integer.
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