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Is it better to reuse a StringBuilder in a loop?
...0) is far and away the most efficient answer. StringBuilder is backed by a char array and is mutable. At the point .toString() is called, the char array is copied and is used to back an immutable string. At this point, the mutable buffer of StringBuilder can be re-used, simply by moving the insertio...
C library function to perform sort
...return 1;
if (f < s) return -1;
return 0;
}
int main(int argc, char* argv[])
{
int x[] = {4,5,2,3,1,0,9,8,6,7};
qsort (x, sizeof(x)/sizeof(*x), sizeof(*x), comp);
for (int i = 0 ; i < 10 ; i++)
printf ("%d ", x[i]);
return 0;
}
...
How does the main() method work in C?
... platform-specific variant
can be handled. */
extern int main(int argc, char **argv, char **envp);
void __start(void)
{
/* This is the real startup function for the executable.
It performs a bunch of library initialization. */
/* ... */
/* And then: */
exit(main(argc_from_somewher...
Split string on the first white space occurrence
...lit(/\s(?=\S+$)/).reverse().map(reverse)
or maybe
re = /^\S+\s|.*/g;
[].concat.call(re.exec(str), re.exec(str))
2019 update: as of ES2018, lookbehinds are supported:
str = "72 tocirah sneab"
s = str.split(/(?<=^\S+)\s/)
console.log(s)
...
Evil Mode best practice? [closed]
... 'evil-end-of-line)
(define-key evil-normal-state-map "\C-f" 'evil-forward-char)
(define-key evil-insert-state-map "\C-f" 'evil-forward-char)
(define-key evil-insert-state-map "\C-f" 'evil-forward-char)
(define-key evil-normal-state-map "\C-b" 'evil-backward-char)
(define-key evil-insert-state-map "...
Replacing column values in a pandas DataFrame
...'] could be 'male', 'female' or 'neutral', do something like this:
w = pd.concat([w, pd.get_dummies(w['female'], drop_first = True)], axis = 1])
w.drop('female', axis = 1, inplace = True)
Then you are left with two new columns giving you the dummy coding of 'female' and you got rid of the column ...
Can I escape html special chars in javascript?
...lay a text to HTML by a javascript function. How can I escape html special chars in JS? Is there an API ?
15 Answers
...
Drop all duplicate rows across multiple columns in Python Pandas
... much clearer, therefore:
In [352]:
DG=df.groupby(['A', 'C'])
print pd.concat([DG.get_group(item) for item, value in DG.groups.items() if len(value)==1])
A B C
2 foo 1 B
3 bar 1 A
[2 rows x 3 columns]
shar...
Regex: match everything but specific pattern
...oo):
Lookahead-based solution for NFAs:
^(?!foo).*$
^(?!foo)
Negated character class based solution for regex engines not supporting lookarounds:
^(([^f].{2}|.[^o].|.{2}[^o]).*|.{0,2})$
^([^f].{2}|.[^o].|.{2}[^o])|^.{0,2}$
a string ending with a specific pattern (say, no world. at the end):...
Remove non-utf8 characters from string
Im having a problem with removing non-utf8 characters from string, which are not displaying properly. Characters are like this 0x97 0x61 0x6C 0x6F (hex representation)
...