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Why doesn't Python have a sign function?
...y removed and replaced by sign! Have you never implemented a class with a __cmp__ method? Have you never called cmp and specified a custom comparator function?
In summary, I've found myself wanting a sign function too, but copysign with the first argument being 1 will work just fine. I disagree ...
Are types like uint32, int32, uint64, int64 defined in any stdlib header?
...
The C99 stdint.h defines these:
int8_t
int16_t
int32_t
uint8_t
uint16_t
uint32_t
And, if the architecture supports them:
int64_t
uint64_t
There are various other integer typedefs in stdint.h as well.
If you're stuck without a C99 environment then you sho...
How can a LEFT OUTER JOIN return more records than exist in the left table?
...
Table1 Table2
_______ _________
1 2
2 2
3 5
4 6
SELECT Table1.Id, Table2.Id FROM Table1 LEFT OUTER JOIN Table2 ON Table1.Id=Table2.Id
Resu...
MongoDB: Combine data from multiple collections into one..how?
...ns). You need to have some key in both collections that you can use as an _id.
For example, let's say you have a users collection and a comments collection and you want to have a new collection that has some user demographic info for each comment.
Let's say the users collection has the following ...
std::enable_if to conditionally compile a member function
...rying to get a simple example to work to understand how to use std::enable_if . After I read this answer , I thought it shouldn't be too hard to come up with a simple example. I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
...
What is a mixin, and why are they useful?
... and `==`,
but this class does NOT implement those methods."""
def __ne__(self, other):
return not (self == other)
def __lt__(self, other):
return self <= other and (self != other)
def __gt__(self, other):
return not self <= other
def __ge__(self, ot...
Replacing Spaces with Underscores
I have a PHP Script that users will enter a name like: Alex_Newton ,
12 Answers
12
...
What is the purpose of Flask's context stacks?
...ing" example:
from werkzeug.wsgi import DispatcherMiddleware
from frontend_app import application as frontend
from backend_app import application as backend
application = DispatcherMiddleware(frontend, {
'/backend': backend
})
Notice that there are two completely different Flask applicat...
How do I create an average from a Ruby array?
...
Try this:
arr = [5, 6, 7, 8]
arr.inject{ |sum, el| sum + el }.to_f / arr.size
=> 6.5
Note the .to_f, which you'll want for avoiding any problems from integer division. You can also do:
arr = [5, 6, 7, 8]
arr.inject(0.0) { |sum, el| sum + el } / arr.size
=> 6.5
You can define it...
Checking if form has been submitted - PHP
...
For general check if there was a POST action use:
if (!empty($_POST))
EDIT: As stated in the comments, this method won't work for in some cases (e.g. with check boxes and button without a name). You really should use:
if ($_SERVER['REQUEST_METHOD'] == 'POST')
...