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Fast way to get image dimensions (not filesize)
...xImageString .= sprintf("%02x", ord($ByteStream[$i]));
if ($Salto==64){
$this->HexImageString .= "\n";
$Salto = 0;
}
}
}
}
private function Byte2PosInt($Byte08,$Byte00) {
return ((ord($Byte08) & 0xFF) << 8)|((ord($Byte00) & 0xF...
What's the difference between emulation and simulation? [duplicate]
...+2 = 4 etc
Emulation tests the functionality on the specific environment (64-bit, 16-bit, fingers and toes).
Here is a food example:
You have two pieces of bread, one knife, peanut butter and jelly and will be giving them to a kindergartner.
You write instructions on how to make a sandwich.
In...
How to round the minute of a datetime object
...-01-01 01:03:34.285714285
7 2019-01-01 01:04:00.000000000
dtype: datetime64[ns]
>>> ts.dt.round('1min')
0 2019-01-01 01:01:00
1 2019-01-01 01:01:00
2 2019-01-01 01:02:00
3 2019-01-01 01:02:00
4 2019-01-01 01:03:00
5 2019-01-01 01:03:00
6 2019-01-01 01:04:00
7 2019-01-01 0...
An efficient way to transpose a file in Bash
...s slightly faster than awk - 350.103s vs. 369.410s I was using perl 5.8.8 64bit
– Federico Giorgi
Nov 16 '09 at 10:18
1
...
How to sum up elements of a C++ vector?
...rder: #include <numeric> and std::accumulate(v.begin(), v.end(), (int64_t)0);. Notice that the type of the initial accumulator value is used as the accumulator type, so if you want to sum 8-bit elements into a 64-bit result, that's how you do it.
– Peter Cordes
...
How do I change the color of radio buttons?
...
Updating from @markreyes: Works in Chrome (64-bit 73.0.3683.75), works somewhat in Safari (12.0.3), and doesn't work in Firefox (64-bit 65.0.1) on March 15 2019.
– jarhill0
Mar 16 '19 at 2:12
...
When to use enumerateObjectsUsingBlock vs. for
...ormat:@"%d", i];
}
int i;
__block NSUInteger length;
i = 1000 * 1000;
uint64_t a1 = mach_absolute_time();
while (--i > 0) {
for (NSString *s in arr) {
length = s.length;
}
}
NSLog(@"For-in %llu", mach_absolute_time()-a1);
i = 1000 * 1000;
uint64_t b1 = mach_absolute_time();
whil...
gdb: how to print the current line or find the current line number?
...
kumar_m_kirankumar_m_kiran
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...
How can you check which options vim was compiled with?
...cc -c -I. -D_FORTIFY_SOURCE=0 -Iproto -DHAVE_CONFIG_H -arch i386 -arch x86_64 -g -Os -pipe
Linking: gcc -arch i386 -arch x86_64 -o vim -lncurses
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Why is there huge performance hit in 2048x2048 versus 2047x2047 array multiplication?
...n your cache. L is always power of 2.
The six comes from fact that 2^6 == 64 bytes is standard size of cache line.
Now what does this mean? Well it means that if I have address X and address Y and
(X >> 6) - (Y >> 6) is divisible by L (i.e. some large power of 2), they will be stored ...