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Generate array of all letters and digits
...g ruby, is it possible to make an array of each letter in the alphabet and 0-9 easily?
7 Answers
...
How to read the content of a file to a string in C?
...-codes for fseek, ftell and fread. (omitted for clarity).
char * buffer = 0;
long length;
FILE * f = fopen (filename, "rb");
if (f)
{
fseek (f, 0, SEEK_END);
length = ftell (f);
fseek (f, 0, SEEK_SET);
buffer = malloc (length);
if (buffer)
{
fread (buffer, 1, length, f);
}
fclo...
How to smooth a curve in the right way?
...bove.
import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0,2*np.pi,100)
y = np.sin(x) + np.random.random(100) * 0.2
yhat = savitzky_golay(y, 51, 3) # window size 51, polynomial order 3
plt.plot(x,y)
plt.plot(x,yhat, color='red')
plt.show()
UPDATE: It has come to my attention t...
Simple way to create matrix of random numbers
...
Take a look at numpy.random.rand:
Docstring: rand(d0, d1, ..., dn)
Random values in a given shape.
Create an array of the given shape and propagate it with random
samples from a uniform distribution over [0, 1).
>>> import numpy as np
>>> np....
Knight's Shortest Path on Chessboard
...ves are connected (value=1), and unavailable moves are disconnected (value=0), the sparse matrix would be like:
(a1,b3)=1,
(a1,c2)=1,
.....
And the shortest path of two points in a graph can be found using http://en.wikipedia.org/wiki/Dijkstra's_algorithm
Pseudo-code from wikipedia-page:
func...
Turn a number into star rating display using jQuery and CSS
...tars, span.stars span {
display: block;
background: url(stars.png) 0 -16px repeat-x;
width: 80px;
height: 16px;
}
span.stars span {
background-position: 0 0;
}
Image
(source: ulmanen.fi)
Note: do NOT hotlink to the above image! Copy the file to your own server and u...
Check that an email address is valid on iOS [duplicate]
...ng
{
BOOL stricterFilter = NO; // Discussion http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/
NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
NSString *ema...
Tetris-ing an array
...
answered Jul 18 '10 at 13:05
starbluestarblue
50.3k1414 gold badges8484 silver badges142142 bronze badges
...
Geometric Mean: is there a built-in?
...ositive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log(x[x > 0]), na.rm=na.rm) / length(x))
}
Thanks to @ben-bolker for noting the na.rm pass-through and @Gregor for making sure it works correctly.
I think some of the comments are related to a false-equivalency of NA values in the d...
How do I apply CSS3 transition to all properties except background-position?
...
Here's a solution that also works on Firefox:
transition: all 0.3s ease, background-position 1ms;
I made a small demo: http://jsfiddle.net/aWzwh/
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