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What is the rationale for all comparisons returning false for IEEE754 NaN values?
... are not real numbers, and floating-point arithmetic does not satisfy the axioms of real arithmetic. Trichotomy is not the only property of real arithmetic that does not hold for floats, nor even the most important. For example:
Addition is not associative.
The distributive law does not hold.
Th...
Why do people say there is modulo bias when using a random number generator?
...am going to post one here which will hopefully help people understand why exactly there is "modulo bias" when using a random number generator, like rand() in C++.
...
What's the difference between std::move and std::forward
... with "t" being template param is special, and adjusts "t" to be
(for example) "int &" or non-ref "int" so std::forward knows what to do. */
void forwarding( t && arg ) {
std::cout << "via std::forward: ";
overloaded( std::forward< t >( arg ) );
std::cout <...
Learning Python from Ruby; Differences and Similarities
...es from the outer scope.
Python has list comprehensions, which are pretty expressive. For example, if you have a list of numbers, you can write
[x*x for x in values if x > 15]
to get a new list of the squares of all values greater than 15. In Ruby, you'd have to write the following:
values....
Intelligent point label placement in R
...oblem:
I did this by hand in Preview (very basic PDF/image viewer on OS X) in just a few minutes. (Edit: The workflow was exactly what you'd expect: I saved the plot as a PDF from R, opened it in Preview and created textboxes with the desired labels (9pt Helvetica) and then just dragged them arou...
How to profile a bash shell script slow startup?
...like to begin a trace in any Bash script):
PS4='+ $(date "+%s.%N")\011 '
exec 3>&2 2>/tmp/bashstart.$$.log
set -x
add
set +x
exec 2>&3 3>&-
at the end of ~/.bashrc (or at the end of the section of any Bash script you'd like tracing to stop). The \011 is an octal tab cha...
How can I convert JSON to CSV?
......]
Here is my code to generate CSV from that:
import csv
import json
x = """[
{
"pk": 22,
"model": "auth.permission",
"fields": {
"codename": "add_logentry",
"name": "Can add log entry",
"content_type": 8
}
},
{
...
fatal error: Python.h: No such file or directory
I am trying to build a shared library using a C extension file but first I have to generate the output file using the command below:
...
How to optimize for-comprehensions and loops in Scala?
...he problem in this particular case is that you return from within the for-expression. That in turn gets translated into a throw of a NonLocalReturnException, which is caught at the enclosing method. The optimizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catch is ...
Can't install PIL after Mac OS X 10.9
...
Following worked for me:
ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/System/Library/Frameworks/Tk.framework/Versions/8.5/Headers/X11 /usr/local/include/X11
sudo pip install pil
UPDATE:
But there is more cor...