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How can I limit possible inputs in a HTML5 “number” element?
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@Prasad - If Andy's answer is correct, select it, instead of the most up voted one.
– Moshe
Dec 4 '11 at 14:47
81
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How to read data when some numbers contain commas as thousand separator?
...thod using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(from) as.numeric(gsub(",", "", from) ) )
Then run read.csv like:
DF <- read.csv('your.file.here',
colClasses=c('num.with.commas','factor','character','numeric','num.w...
Memory footprint of Haskell data types
...e) which take 2. GHC actually has a cache of small values of type Int and Char, so in many cases these take no heap space at all. A String only requires space for the list cells, unless you use Chars > 255.
An Int8 has identical representation to Int. Integer is defined like this:
data Integ...
Efficient way to determine number of digits in an integer
...cialization optimization for 8-bit numbers
template <>
int numDigits(char n)
{
// if you have the time, replace this with a static initialization to avoid
// the initial overhead & unnecessary branch
static char x[256] = {0};
if (x[0] == 0) {
for (char c = 1; c != 0...
How do you clear the SQL Server transaction log?
... solution then please comment below
Right click on the database name.
Select Tasks → Shrink → Database
Then click OK!
I usually open the Windows Explorer directory containing the database files, so I can immediately see the effect.
I was actually quite surprised this worked! Normally I'v...
Remove characters from NSString?
... This ONLY works if the 'spaces' are well behaved ASCII value=32 (%20) characters. To remove ALL possible white-space chars use Jim Dovey's solution below.
– Linasses
Apr 28 at 11:23
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What's the magic of “-” (a dash) in command-line parameters?
.../home | aescrypt -e -p apples -o backup_files.tar.aes - because the piping char | should make the presence of the last dash unnecessary. But without the last dash the command fails. Sounds illogical. Can someone please give me a reference where the naked dash meaning in command lines is explained. I...
How does this program work?
...oat is converted to double, as the prototype of printf is int printf(const char*, ...), from 6.5.2.2/7,
The ellipsis notation in a function prototype declarator causes argument type conversion to stop after the last declared parameter. The default argument promotions are performed on trailing ar...
Can I use a binary literal in C or C++?
...namespace std;
int main() {
unsigned short b = BOOST_BINARY( 10010 );
char buf[sizeof(b)*8+1];
printf("hex: %04x, dec: %u, oct: %06o, bin: %16s\n", b, b, b, itoa(b, buf, 2));
cout << setfill('0') <<
"hex: " << hex << setw(4) << b << ", " <<
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Using scanf() in C++ programs is faster than using cin?
...numbers.
iostream version:
#include <iostream>
int main(int argc, char **argv) {
int parity = 0;
int x;
while (std::cin >> x)
parity ^= x;
std::cout << parity << std::endl;
return 0;
}
scanf version:
#include <stdio.h>
int main(int argc, char **a...