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How do I create an average from a Ruby array?
...void integer division or your results will be wrong. Also, this isn't generally applicable to every possible element type (obviously, an average only makes sense for things that can be averaged). But if you want to go that route, use this:
class Array
def sum
inject(0.0) { |result, el| result...
How to append contents of multiple files into one file
... should be >> right ? and also why is there a newline before all the text in my 0.txt file ?
– Steam
Aug 2 '13 at 0:00
2
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How do I catch a numpy warning like it's an exception (not just for testing)?
...ng: divide by zero encountered in divide
array([0])
>>> np.seterr(all='print')
{'over': 'warn', 'divide': 'warn', 'invalid': 'warn', 'under': 'ignore'}
>>> np.array([1])/0 #'print' mode
Warning: divide by zero encountered in divide
array([0])
This means that the warning you see...
Will using 'var' affect performance?
...ay have chosen an Interface or parent type if you were to set the type manually.
Update 8 Years Later
I need to update this as my understanding has changed. I now believe it may be possible for var to affect performance in the situation where a method returns an interface, but you would have used a...
Can you add new statements to Python's syntax?
... a hands-on approach here: I'm going to add an until statement to Python.
All the coding for this article was done against the cutting-edge Py3k branch in the Python Mercurial repository mirror.
The until statement
Some languages, like Ruby, have an until statement, which is the complement to whi...
How to check if all elements of a list matches a condition?
...
The best answer here is to use all(), which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>...
Leaflet - How to find existing markers, and delete markers?
...
Should be a way to collect all of the layers used by Leaflet. :/
– jackyalcine
Aug 1 '12 at 21:39
10
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Why is parenthesis in print voluntary in Python 2.7?
...
In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
unit testing of private functions with mocha and node.js
...
If the function is not exported by the module, it cannot be called by test code outside the module. That's due to how JavaScript works, and Mocha cannot by itself circumvent this.
In the few instances where I determined that testing a private function is the right thing to do, what I'...
How to find where a method is defined at runtime?
...
This is really late, but here's how you can find where a method is defined:
http://gist.github.com/76951
# How to find out where a method comes from.
# Learned this from Dave Thomas while teaching Advanced Ruby Studio
# Makes the cas...