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How to convert a scala.List to a java.util.List?
...1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.collection.mutable.ListBuffer
asList(ListBuffer(List(1,2,3): _*))
val x: java.util.List[Int] = ListBuffer(List(1,2,3): _*)
However, asList in that example is not necessary if the type expected is a Java List,...
How do I do base64 encoding on iOS?
...ve posted it here:
First, you need the mapping tables:
static const char _base64EncodingTable[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const short _base64DecodingTable[256] = {
-2, -2, -2, -2, -2, -2, -2, -2, -2, -1, -1, -2, -1, -1, -2, -2,
-2, -2, -...
How do I find the location of my Python site-packages directory?
...ysconfig module instead:
python3 -c 'import sysconfig; print(sysconfig.get_paths()["purelib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and ...
Running unittest with typical test directory structure
...e TestLoader class).
For example for a directory structure like this:
new_project
├── antigravity.py
└── test_antigravity.py
You can just run:
$ cd new_project
$ python -m unittest test_antigravity
For a directory structure like yours:
new_project
├── antigravity
│ ...
How can I profile Python code line-by-line?
...
I believe that's what Robert Kern's line_profiler is intended for. From the link:
File: pystone.py
Function: Proc2 at line 149
Total time: 0.606656 s
Line # Hits Time Per Hit % Time Line Contents
=================================================...
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...
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...
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...
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)
...
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...