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How to decide font color in white or black depending on background color?
...conversion from sRGB to linear RGB followed by the ITU-R recommendation BT.709 for luminance.
for each c in r,g,b:
c = c / 255.0
if c <= 0.03928 then c = c/12.92 else c = ((c+0.055)/1.055) ^ 2.4
L = 0.2126 * r + 0.7152 * g + 0.0722 * b
The threshold of 0.179 should not be changed since...
How to change the color of an svg element?
...4.79-104.675,21.618-143.081
c0.274-1.542,1.615-2.669,3.181-2.669h0.008c1.709,0,3.164,1.243,3.431,2.932l18.933,119.904L382.816,265.785z"/>
</svg>
<image class="my-svg-alternate" width="96" height="96" src="ppngfallback.png" />
You can inline your SVG, tag your fallback ima...
Formula to determine brightness of RGB color
... for is the RGB -> Luma conversion formula.
Photometric/digital ITU BT.709:
Y = 0.2126 R + 0.7152 G + 0.0722 B
Digital ITU BT.601 (gives more weight to the R and B components):
Y = 0.299 R + 0.587 G + 0.114 B
If you are willing to trade accuracy for perfomance, there are two approximation ...
Printing 1 to 1000 without loop or conditionals
...t: Added '&' so it will consider the address hence evading the pointer errors.
This version of the above in standard C, since it doesn't rely on arithmetic on function pointers:
#include <stdio.h>
#include <stdlib.h>
void f(int j)
{
static void (*const ft[2])(int) = { f, exit ...
Find the Smallest Integer Not in a List
...have at most 134,217,728 numbers in it. But there are 264 = 18,446,744,073,709,551,616 possible numbers. So the probability that zero is in the list is 1 in 137,438,953,472.
In contrast, my odds of being struck by lightning this year are 1 in 700,000. And my odds of getting hit by a meteorite are a...
MySQL vs MongoDB 1000 reads
...----------------------------------------------
1000000 872.709µs
SELECT & DISPLAY
------------------------------------------------
num of rows time taken
------------------------------------------------
1000000 20.717354746s
UP...
Are list-comprehensions and functional functions faster than “for loops”?
...umtime percall filename:lineno(function)
1000000 0.318 0.000 0.709 0.000 profiling.py:18(list_comp)
1000000 0.261 0.000 0.261 0.000 profiling.py:19(<listcomp>)
1000000 0.131 0.000 0.131 0.000 {built-in method builtins.sum}
1000000 0.027 0.000 ...
Structure padding and packing
...
@CiroSantilli709大抓捕六四事件法轮功, it was on gimp, but I guess I'd have saved some time doing it on paint though haha
– IanC
Jul 30 '17 at 22:21
...
Constant Amortized Time
... fits 4,294,967,296 count of money
...
64th room size= fits 18,446,744,073,709,551,616 count of money
Why is this better? Because it looks to grow slowly in the begin, and faster later, that is, compared to the amount of memory in our RAM.
This is helpful because, in the first case though it is ...
Fastest way to list all primes below N
...or a,b in itertools.izip_longest(f1(num),f2(num))]):
sys.exit("Error: %s(%s) != %s(%s)"%(f1.func_name,num,f2.func_name,num))
n=1000000
test(sieveOfAtkin,sieveOfEratosthenes,n)
test(sieveOfAtkin,ambi_sieve,n)
test(sieveOfAtkin,ambi_sieve_plain,n)
test(sieveOfAtkin,su...