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Python exit commands - why so many and when should each be used?
...tus 1. Note that portable programs are limited to exit status codes in the range 0-255, if you raise SystemExit(256) on many systems this will get truncated and your process will actually exit with status 0.
Footnotes
* Actually, quit() and exit() are callable instance objects, but I think it's ok...
Matplotlib 2 Subplots, 1 Colorbar
...5, 0.7])
fig.colorbar(im, cax=cbar_ax)
plt.show()
Note that the color range will be set by the last image plotted (that gave rise to im) even if the range of values is set by vmin and vmax. If another plot has, for example, a higher max value, points with higher values than the max of im will s...
Iterate over object attributes in python
...s(IterMixin): pass
...
>>> yc = YourClass()
>>> yc.one = range(15)
>>> yc.two = 'test'
>>> dict(yc)
{'one': [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14], 'two': 'test'}
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Accessing the index in 'for' loops?
...etimes more commonly (but unidiomatically) found in Python:
for index in range(len(items)):
print(index, items[index])
Use the Enumerate Function
Python's enumerate function reduces the visual clutter by hiding the accounting for the indexes, and encapsulating the iterable into another ite...
How to generate a random string of a fixed length in Go?
...func RandStringRunes(n int) string {
b := make([]rune, n)
for i := range b {
b[i] = letterRunes[rand.Intn(len(letterRunes))]
}
return string(b)
}
2. Bytes
If the characters to choose from and assemble the random string contains only the uppercase and lowercase letters of t...
Will using 'var' affect performance?
...e, if you have this method:
IList<int> Foo()
{
return Enumerable.Range(0,10).ToList();
}
Consider these three lines of code to call the method:
List<int> bar1 = Foo();
IList<int> bar = Foo();
var bar3 = Foo();
All three compile and execute as expected. However, the first two ...
Get key by value in dictionary
...n each method 100000 times:
Method 1:
>>> profile.run("for i in range(0,100000): method1(list,16)")
200004 function calls in 1.173 seconds
Method 2:
>>> profile.run("for i in range(0,100000): method2(list,16)")
200004 function calls in 1.222 seconds
Method 3:
>...
How to elegantly check if a number is within a range?
...
There are a lot of options:
int x = 30;
if (Enumerable.Range(1,100).Contains(x))
//true
if (x >= 1 && x <= 100)
//true
Also, check out this SO post for regex options.
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...
Python: List vs Dict for look up table
... sets, running python 2.7.3 on an i7 CPU on linux:
python -mtimeit -s 'd=range(10**7)' '5*10**6 in d'
10 loops, best of 3: 64.2 msec per loop
python -mtimeit -s 'd=dict.fromkeys(range(10**7))' '5*10**6 in d'
10000000 loops, best of 3: 0.0759 usec per loop
python -mtimeit -s 'from sets import Set...
Difference between signed / unsigned char [duplicate]
...E2;
BYTE1 a;
BYTE2 b;
For variable a, only 7 bits are available and its range is (-127 to 127) = (+/-)2^7 -1.
For variable b all 8 bits are available and the range is 0 to 255 (2^8 -1).
If you use char as character, "unsigned" is completely ignored by the compiler just as comments are removed f...