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Intersection of two lists in Bash
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291
comm -12 <(ls 1) <(ls 2)
...
With bash, how can I pipe standard error into another process?
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172
There is also process substitution. Which makes a process substitute for a file.
You can send s...
Should I use a data.frame or a matrix?
...e the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer to ...
If vs. Switch Speed
...
answered Jan 14 '09 at 23:16
Konrad RudolphKonrad Rudolph
461k118118 gold badges863863 silver badges11101110 bronze badges
...
What is the bower (and npm) version syntax?
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342
In a nutshell, the syntax for Bower version numbers (and NPM's) is called SemVer, which is short...
How to pip install a package with min and max version range?
... install a package with both a minimum version ( pip install package>=0.2 ) and a maximum version which should never be installed (theoretical api: pip install package<0.3 ).
...
LINQ where vs takewhile
... and find all elements matching the condition
var intList = new int[] { 1, 2, 3, 4, 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Conso...
Python Matplotlib figure title overlaps axes label when using twiny
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248
I'm not sure whether it is a new feature in later versions of matplotlib, but at least for 1.3...
Difference between dispatch_async and dispatch_sync on serial queue?
....
for this code
dispatch_async(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_async(_serialQueue, ^{ printf("3"); });
printf("4");
It may print 2413 or 2143 or 1234 but 1 always before 3
for this code
dispatch_sync(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_sync(_serialQu...
Python unittests in Jenkins?
...ample tests:
tests.py:
# tests.py
import random
try:
import unittest2 as unittest
except ImportError:
import unittest
class SimpleTest(unittest.TestCase):
@unittest.skip("demonstrating skipping")
def test_skipped(self):
self.fail("shouldn't happen")
def test_pass(sel...