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How do I time a method's execution in Java?
... = System.nanoTime();
long duration = (endTime - startTime); //divide by 1000000 to get milliseconds.
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data.frame rows to a list
...eresting solutions:
data("Batting", package = "Lahman")
x <- Batting[1:10000, 1:10]
library(benchr)
library(purrr)
benchmark(
split = split(x, seq_len(.row_names_info(x, 2L))),
mapply = .mapply(function(...) structure(list(...), class = "data.frame", row.names = 1L), x, NULL),
purrr ...
Array vs. Object efficiency in JavaScript
... f = 0; f < 2000; f++) {
var newNo = Math.floor(Math.random()*60000+10000);
if (!o[newNo.toString()]) o[newNo.toString()] = {id: newNo, name: 'test'};
if (!a2[newNo]) a2[newNo] = {id: newNo, name: 'test' };
a1.push({id: newNo, name: 'test'});
}
Original Post - Explanation
Th...
(Built-in) way in JavaScript to check if a string is a valid number
...Examples
isNaN(123) // false
isNaN('123') // false
isNaN('1e10000') // false (This translates to Infinity, which is a number)
isNaN('foo') // true
isNaN('10px') // true
Of course, you can negate this if you need to. For example, to implement the IsNumeric example you ga...
How to put a unicode character in XAML?
...32 character, like the musical notes in the Symbola font which are above 0x10000?
– Ruud van Gaal
Jan 29 '18 at 19:38
...
What is the MySQL VARCHAR max size?
...s.
In your case it may possible that when you are trying to set more than 10000 it is exceeding more than 65,535 and mysql will gives the error.
For more information: https://dev.mysql.com/doc/refman/5.0/en/column-count-limit.html
blog with example: http://goo.gl/Hli6G3
...
RGB to hex and hex to RGB
...epresentation. Likewise r << 16 adds 4 zeroes. Adding 1 << 24 (1000000 in hex) ensures that the hex representation is left-padded with any required zeroes once the leading 1 is stripped off using slice(). For example, if r and g were both zero and b was 51, ((r << 16) + (g <<...
How do you reverse a string in place in C or C++?
...p < --q)
switch( (*q & 0xF0) >> 4 ) {
case 0xF: /* U+010000-U+10FFFF: four bytes. */
SWP(*(q-0), *(q-3));
SWP(*(q-1), *(q-2));
q -= 3;
break;
case 0xE: /* U+000800-U+00FFFF: three bytes. */
SWP(*(q-0), *(q-2));
q -= 2;
break;
cas...
How to make a flat list out of list of lists?
...,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l, [])'
1000 loops, best of 3: 969 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'reduce(lambda ...
How to set initial size of std::vector?
...with the former, you just address the pointers, so something like whatever[10000] = somepointer;, where the latter requires you to push_back each pointer you add. At least if you're accustomed to vector, the latter is probably simpler and more natural.
– Jerry Coffin
...