大约有 47,000 项符合查询结果（耗时：0.0545秒） [XML]
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 to remove the first Item from a list?
I have the list [0, 1, 2, 3, 4] I'd like to make it into [1, 2, 3, 4] . How do I go about this?
10 Answers
...
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?
...
103
You can use gridspec to control the spacing between axes. There's more information here.
impo...
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: ...
MySQL IF NOT NULL, then display 1, else display 0
...
Instead of COALESCE(a.addressid,0) AS addressexists, use CASE:
CASE WHEN a.addressid IS NOT NULL
THEN 1
ELSE 0
END AS addressexists
or the simpler:
(a.addressid IS NOT NULL) AS addressexists
This works because TRUE is displayed as 1 in ...
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 ...
Convert a list of data frames into one data frame
...
answered Feb 27 '18 at 20:05
joekliegjoeklieg
1,50411 gold badge55 silver badges33 bronze badges
...
How to initialize an array's length in JavaScript?
..., e.g.
var data = [];
var length = 5; // user defined length
for(var i = 0; i < length; i++) {
data.push(createSomeObject());
}
share
|
improve this answer
|
follow...
Fastest way to reset every value of std::vector to 0
...at's the fastest way to reset every value of a std::vector<int> to 0 and keeping the vectors initial size ?
6 Answ...