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How to check if hex color is “too black”?
...Int(c, 16); // convert rrggbb to decimal
var r = (rgb >> 16) & 0xff; // extract red
var g = (rgb >> 8) & 0xff; // extract green
var b = (rgb >> 0) & 0xff; // extract blue
var luma = 0.2126 * r + 0.7152 * g + 0.0722 * b; // per ITU-R BT.709
if (luma < 40) {
...
How to remove gaps between subplots in matplotlib?
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103
You can use gridspec to control the spacing between axes. There's more information here.
impo...
Java - get pixel array from image
...ation I was able to reduce the time of processing the pixels by more than 90% by just switching from the first approach to the second!
Here is a comparison I've setup to compare the two approaches:
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferByte;
import java.io.IOExceptio...
How do you make an array of structs in C?
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107
#include<stdio.h>
#define n 3
struct body
{
double p[3];//position
double v[3];//...
Count work days between two dates
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306
For workdays, Monday to Friday, you can do it with a single SELECT, like this:
DECLARE @StartD...
Why 0 is true but false is 1 in the shell?
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10 Answers
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Position of least significant bit that is set
... position of the least significant bit that is set in an integer, e.g. for 0x0FF0 it would be 4.
22 Answers
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...hould work:
SELECT CASE WHEN myfield~E'^\\d+$' THEN myfield::integer ELSE 0 END FROM mytable;
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Two-dimensional array in Swift
...Int]] = []
OR if you need an array of predefined size (as mentioned by @0x7fffffff in comments):
// 2 dimensional array of arrays of Ints set to 0. Arrays size is 10x5
var arr = Array(count: 3, repeatedValue: Array(count: 2, repeatedValue: 0))
// ...and for Swift 3+:
var arr = Array(repeating: ...
Double vs. BigDecimal?
...s a certain precision. Working with doubles of various magnitudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and ...