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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...ase of foldLeft
scala> val intParList: ParSeq[Int] = (1 to 100000).map(_ => scala.util.Random.nextInt()).par
scala> timeMany(1000, intParList.reduce(_ + _))
Took 462.395867 milli seconds
scala> timeMany(1000, intParList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fo...
How to measure time taken between lines of code in python?
...
If you want to measure CPU time, can use time.process_time() for Python 3.3 and above:
import time
start = time.process_time()
# your code here
print(time.process_time() - start)
First call turns the timer on, and second call tells you how many seconds have elapsed.
The...
Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell
...
Using GHC 7.0.3, gcc 4.4.6, Linux 2.6.29 on an x86_64 Core2 Duo (2.5GHz) machine, compiling using ghc -O2 -fllvm -fforce-recomp for Haskell and gcc -O3 -lm for C.
Your C routine runs in 8.4 seconds (faster than your run probably because of -O3)
The Haskell solution runs in...
super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
...nk your python version is 2.X, the super would work when adding this code
__metaclass__ = type
so the code is
__metaclass__ = type
class B:
def meth(self, arg):
print arg
class C(B):
def meth(self, arg):
super(C, self).meth(arg)
print C().meth(1)
...
background function in Python
...
Do something like this:
def function_that_downloads(my_args):
# do some long download here
then inline, do something like this:
import threading
def my_inline_function(some_args):
# do some stuff
download_thread = threading.Thread(target=function_t...
Saving an Object (Data persistence)
...tion of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data.pkl', 'wb') as output:
company1 = Company('banana', 40)
pickle.dump(company1, output, pickle.HIGHEST_PROTOCOL)
...
Resolve build errors due to circular dependency amongst classes
...riting a compiler. And you see code like this.
// file: A.h
class A {
B _b;
};
// file: B.h
class B {
A _a;
};
// file main.cc
#include "A.h"
#include "B.h"
int main(...) {
A a;
}
When you are compiling the .cc file (remember that the .cc and not the .h is the unit of compilation), you ne...
What's the dSYM and how to use it? (iOS SDK)
... 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
1 libswiftCore.dylib 0x000000018f3c9380 closure #1 in closure #1 in closure #1 in _assertionFailure+ 217984 (_:_:file:line:flags:) + 452
2 libswiftCore.d...
Map Tiling Algorithm
...le:Object, degrees:uint):void
{
// http://www.flash-db.com/Board/index.php?topic=18625.0
var midPoint:int = tileDimension/2;
var point:Point=new Point(tile.x+midPoint, tile.y+midPoint);
var m:Matrix=tile.transform.matrix;
m.tx -= point.x;
m.ty -= point.y;
m.rotate (degree...
How do I call setattr() on the current module?
...
import sys
thismodule = sys.modules[__name__]
setattr(thismodule, name, value)
or, without using setattr (which breaks the letter of the question but satisfies the same practical purposes;-):
globals()[name] = value
Note: at module scope, the latter is eq...