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Function for Factorial in Python
... use an iterative approach:
def factorial(n):
fact = 1
for num in range(2, n + 1):
fact *= num
return fact
or a recursive approach:
def factorial(n):
if n < 2:
return 1
else:
return n * factorial(n-1)
Note that the factorial function is only defin...
Saving a Numpy array as an image
...
Remember to scale the values to the right range for PNG, usually 0..255. The value ranges in neural networks are frequently 0..1 or -1..1.
– Tomáš Gavenčiak
Mar 31 '18 at 18:49
...
Counting the Number of keywords in a dictionary in python
... comparison to whatever else your program is doing.
d = {x: x**2 for x in range(1000)}
len(d)
# 1000
len(d.keys())
# 1000
%timeit len(d)
# 41.9 ns ± 0.244 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)
%timeit len(d.keys())
# 83.3 ns ± 0.41 ns per loop (mean ± std. dev. of 7 ...
Read text file into string array (and write)
...
defer file.Close()
w := bufio.NewWriter(file)
for _, line := range lines {
fmt.Fprintln(w, line)
}
return w.Flush()
}
func main() {
lines, err := readLines("foo.in.txt")
if err != nil {
log.Fatalf("readLines: %s", err)
}
for i, line := range lin...
Min/Max-value validators in asp.net mvc
...on using attributes in asp.net mvc is really nice. I have been using the [Range(min, max)] validator this far for checking values, like e.g.:
...
Minimizing NExpectation for a custom distribution in Mathematica
...df[x] looks like
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x]*x, {x, 0, .3}, PlotRange -> All]
and the expected value is
NIntegrate[pdf2[3.77, 1.34, -2.65, 0.40, x]*x, {x, 0, \[Infinity]}]
Out= 0.0596504
But since you want the expected value between a start and +inf we need to integrate in this ...
Zip lists in Python
...ts. Each element is a three-tuple.
See for yourself:
In [1]: a = b = c = range(20)
In [2]: zip(a, b, c)
Out[2]:
[(0, 0, 0),
(1, 1, 1),
...
(17, 17, 17),
(18, 18, 18),
(19, 19, 19)]
To find out how many elements each tuple contains, you could examine the length of the first element:
In [3...
Efficient evaluation of a function at every cell of a NumPy array
...lot
perfplot.show(
setup=lambda n: np.random.rand(n,n)[::2,::2],
n_range=[2**k for k in range(0,12)],
kernels=[
f,
vf,
nb_vf
],
logx=True,
logy=True,
xlabel='len(x)'
)
B. comparison of exp:
import perfplot
import numexpr as ne # using ...
Keyboard Interrupts with python's multiprocessing Pool
...ify a timeout. To do that, replace
results = pool.map(slowly_square, range(40))
with
results = pool.map_async(slowly_square, range(40)).get(9999999)
or similar.
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How to Get the Title of a HTML Page Displayed in UIWebView?
...g:NSASCIIStringEncoding error:nil];
NSString * start = @"<title>";
NSRange range1 = [htmlCode rangeOfString:start];
NSString * end = @"</title>";
NSRange range2 = [htmlCode rangeOfString:end];
NSString * subString = [htmlCode substringWithRange:NSMakeRange(range1.location + 7, range2.l...