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How to use the PI constant in C++
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On some (especially older) platforms (see the comments below) you might need to
#define _USE_MATH_DEFINES
and then include the necessary header file:
#include <math.h>
and the value of pi can be accessed via:
M_PI
In my math....
django urls without a trailing slash do not redirect
...ost.". "The APPEND_SLASH setting is only used if CommonMiddleware is installed...". I prefer Michael Gendin's answer for a cleaner solution.
– Wtower
Feb 11 '15 at 9:26
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Any gotchas using unicode_literals in Python 2.6?
...wo.name
The output of running python one.py is:
Traceback (most recent call last):
File "one.py", line 5, in <module>
print name + two.name
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 4: ordinal not in range(128)
In this example, two.name is an utf-8 encoded...
Make elasticsearch only return certain fields?
...fields from there. May impact performance if returned data is relatively small to the size of a whole document.
– Zaar Hai
Aug 18 '13 at 10:19
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Remove HTML Tags in Javascript with Regex
I am trying to remove all the html tags out of a string in Javascript.
Heres what I have... I can't figure out why its not working....any know what I am doing wrong?
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Running a specific test case in Django when your app has a tests directory
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Checkout django-nose. It allows you to specify tests to run like:
python manage.py test another.test:TestCase.test_method
or as noted in comments, use the syntax:
python manage.py test another.test.TestCase.test_method
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What is the advantage of GCC's __builtin_expect in if else statements?
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I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
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after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...
How to deal with SettingWithCopyWarning in Pandas?
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The SettingWithCopyWarning was created to flag potentially confusing "chained" assignments, such as the following, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2...
Replace multiple characters in one replace call
... just have to chain. However, you could add a prototype:
String.prototype.allReplace = function(obj) {
var retStr = this;
for (var x in obj) {
retStr = retStr.replace(new RegExp(x, 'g'), obj[x]);
}
return retStr;
};
console.log('aabbaabbcc'.allReplace({'a': 'h', 'b': 'o'}))...
Try catch statements in C
... exceptions but you can simulate them to a degree with setjmp and longjmp calls.
static jmp_buf s_jumpBuffer;
void Example() {
if (setjmp(s_jumpBuffer)) {
// The longjmp was executed and returned control here
printf("Exception happened here\n");
} else {
// Normal code execution s...