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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...rList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fold
Now this is where it gets a little closer to the FP / mathematical roots, and a little trickier to explain. Reduce is defined formally as part of the MapReduce paradigm, which deals with orderless collections (multisets), Fo...
What is a None value?
...right and F = None resets F to its original state, then it should be there now, and we should see
>>> print(F)
None
like we do after we type F = None and put the sticker on None.
So that's all that's going on. In reality, Python comes with some stickers already attached to objects (b...
How to add Google Analytics Tracking ID to GitHub Pages
Could be a simple question but I am full of doubts right now about adding Google Analytics Tracking ID to GitHub page .
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How can I output leading zeros in Ruby?
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If the maximum number of digits in the counter is known (e.g., n = 3 for counters 1..876), you can do
str = "file_" + i.to_s.rjust(n, "0")
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What would a “frozen dict” be?
...to want such a type is when memoizing function calls for functions with unknown arguments. The most common solution to store a hashable equivalent of a dict (where the values are hashable) is something like tuple(sorted(kwargs.iteritems())).
This depends on the sorting not being a bit insane. Pyth...
if A vs if A is not None:
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@cedbeu, Seems to depend on the value of A. I tested now python -m timeit -s"a=0" "if a: pass" "else: pass" is faster than python -m timeit -s"a=0" "if a is None: pass" "else: pass" but python -m timeit -s"a=1" "if a: pass" "else: pass" is slower. Might be platform dependant, s...
What are dictionary view objects?
...eritems() returns an iterator over the dictionary’s (key, value) pairs.
Now take the following example to see the difference between an interator of dict and a view of dict
>>> d = {"x":5, "y":3}
>>> iter = d.iteritems()
>>> del d["x"]
>>> for i in iter: print...
What are the best JVM settings for Eclipse? [closed]
...ill still look for the "Sun Microsystems" string, but with 6u21b7, it will now work - again.
For now, I still keep the -XX:MaxPermSize version (because I have no idea when everybody will launch eclipse the right JDK).
Implicit `-startup` and `--launcher.library`
Contrary to the previous settin...
Where should signal handlers live in a django project?
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Thanks for that - good to know. I'm logging all logins using this method (recording IP / user agent), and haven't had any duplicates so far - although that doesn't mean a small change down the line won't cause a problem!
– Hugo Ro...
JavaScript pattern for multiple constructors
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I've rolled the same pattern in node.js too now with: npmjs.com/package/extend
– Jacob McKay
Jun 17 '16 at 16:37
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