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Avoid trailing zeroes in printf()
...ormat specifiers. The closest you could get would be:
printf("%.6g", 359.013); // 359.013
printf("%.6g", 359.01); // 359.01
but the ".6" is the total numeric width so
printf("%.6g", 3.01357); // 3.01357
breaks it.
What you can do is to sprintf("%.20g") the number to a string buffer then man...
How can I convert a Unix timestamp to DateTime and vice versa?
...
1059
Here's what you need:
public static DateTime UnixTimeStampToDateTime( double unixTimeStamp )
...
What's the fastest way to loop through an array in JavaScript?
...yntactically obvious).
A standard for-loop with length caching
var i = 0, len = myArray.length;
while (i < len) {
// your code
i++
}
I would say, this is definitely a case where I applaud JavaScript engine developers. A runtime should be optimized for clarity, not cle...
What does `kill -0 $pid` in a shell script do?
Basically, what signal does '0' represent, because here I see SIGNAL numbers starting from 1.
6 Answers
...
Most efficient way to create a zero filled JavaScript array?
...duces Array.prototype.fill. It can be used like this:
new Array(len).fill(0);
Not sure if it's fast, but I like it because it's short and self-describing.
It's still not in IE (check compatibility), but there's a polyfill available.
...
Convert RGB to RGBA over white
...ha value.
Example:
152 converts to an alpha value of (255 - 152) / 255 ~ 0.404
152 scales using (152 - 152) / 0.404 = 0
177 scales using (177 - 152) / 0.404 ~ 62
202 scales using (202 - 152) / 0.404 ~ 123
So, rgb(152, 177, 202) displays as rgba(0, 62, 123, .404).
I have verified in Photoshop t...
Showing the same file in both columns of a Sublime Text window
...|
edited Oct 22 '16 at 3:40
answered May 30 '14 at 23:33
Ma...
What is the most efficient/elegant way to parse a flat table into a tree?
...
Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* F...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...
Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...
How To: Best way to draw table in console app (C#)
...ring text, int width)
{
text = text.Length > width ? text.Substring(0, width - 3) + "..." : text;
if (string.IsNullOrEmpty(text))
{
return new string(' ', width);
}
else
{
return text.PadRight(width - (width - text.Length) / 2).PadLeft(width);
}
}
...