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All falsey values in JavaScript
...ypeof as undefined. It was a Microsoft-proprietory function in IE before IE11, and was added to the HTML spec as a "willful violation of the JavaScript specification" so that sites written for IE wouldn't break on trying to access, for example, document.all.something; it's falsy because if (document...
Regular expressions in C: examples?
...s):
#include <regex.h>
regex_t regex;
int reti;
char msgbuf[100];
/* Compile regular expression */
reti = regcomp(&regex, "^a[[:alnum:]]", 0);
if (reti) {
fprintf(stderr, "Could not compile regex\n");
exit(1);
}
/* Execute regular expression */
reti = regexec(&regex,...
iOS UIImagePickerController result image orientation after upload
I am testing my iPhone application on an iOS 3.1.3 iPhone. I am selecting/capturing an image using a UIImagePickerController :
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Why does parseInt(1/0, 19) return 18?
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1294
The result of 1/0 is Infinity.
parseInt treats its first argument as a string which means fi...
Matplotlib different size subplots
...np
import matplotlib.pyplot as plt
# generate some data
x = np.arange(0, 10, 0.2)
y = np.sin(x)
# plot it
f, (a0, a1) = plt.subplots(1, 2, gridspec_kw={'width_ratios': [3, 1]})
a0.plot(x, y)
a1.plot(y, x)
f.tight_layout()
f.savefig('grid_figure.pdf')
...
Why does 0.ToString(“#.##”) return an empty string instead of 0.00 or at least 0?
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185
# in the string format indicate that the value is optional. If you wish to get the output 0.00...
Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?
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197
Here is a fairly concise way to do this:
static readonly string[] SizeSuffixes =
...
Interpolating a string into a regex
...
answered Sep 29 '08 at 18:53
Jonathan LonowskiJonathan Lonowski
108k3131 gold badges188188 silver badges191191 bronze badges
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What is Weak Head Normal Form?
...
These expressions are all in normal form:
42
(2, "hello")
\x -> (x + 1)
These expressions are not in normal form:
1 + 2 -- we could evaluate this to 3
(\x -> x + 1) 2 -- we could apply the function
"he" ++ "llo" -- we could apply the (++)
(1 + 1, 2 + 2) ...