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Why 0 is true but false is 1 in the shell?
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10 Answers
10
Active
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How do I find out if first character of a string is a number?
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260
Character.isDigit(string.charAt(0))
Note that this will allow any Unicode digit, not just 0-9....
How do I get SUM function in MySQL to return '0' if no values are found?
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307
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
T...
javascript: recursive anonymous function?
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answered Oct 7 '10 at 16:46
PointyPointy
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Is it possible to change only the alpha of a rgba background colour on hover?
... { display: block; position: relative; }
div { position: absolute; bottom: 0; background-color: rgba(var(--rgb), 0.8); }
a:hover div { background-color: rgba(var(--rgb), 1); }
To understand how this works, see How do I apply opacity to a CSS color variable?
If custom properties are not an option,...
Is R's apply family more than syntactic sugar?
... n < 2 ) n
+ else fibo(n-1) + fibo(n-2)
+ }
> system.time(for(i in 0:26) fibo(i))
user system elapsed
7.48 0.00 7.52
> system.time(sapply(0:26, fibo))
user system elapsed
7.50 0.00 7.54
> system.time(lapply(0:26, fibo))
user system elapsed
7.48 ...
Removing white space around a saved image in matplotlib
...lab flag.)
plt.gca().set_axis_off()
plt.subplots_adjust(top = 1, bottom = 0, right = 1, left = 0,
hspace = 0, wspace = 0)
plt.margins(0,0)
plt.gca().xaxis.set_major_locator(plt.NullLocator())
plt.gca().yaxis.set_major_locator(plt.NullLocator())
plt.savefig("filename.pdf", bbox_inches =...
How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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Initialise a list to a specific length in Python [duplicate]
How do I initialise a list with 10 times a default value in Python?
3 Answers
3
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css3 实现静态图片闪烁效果 - 更多技术 - 清泛网 - 专注C/C++及内核技术
... ease-in-out;
position: absolute;
}
@-webkit-keyframes start {
0%,30% {opacity: 0;-webkit-transform: translate(0,0);}
60% {opacity: 1;-webkit-transform: translate(0,0);}
100% {opacity: 1;-webkit-transform: translate(0,0);}
}
@-moz-keyframes start {
0%,30% {opacity: 0;-mo...