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Why 0 is true but false is 1 in the shell?

... 10 Answers 10 Active ...
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How do I find out if first character of a string is a number?

... 260 Character.isDigit(string.charAt(0)) Note that this will allow any Unicode digit, not just 0-9....
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javascript: recursive anonymous function?

... answered Oct 7 '10 at 16:46 PointyPointy 359k5454 gold badges508508 silver badges567567 bronze badges ...
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How do I get SUM function in MySQL to return '0' if no values are found?

... 307 Use COALESCE to avoid that outcome. SELECT COALESCE(SUM(column),0) FROM table WHERE ... T...
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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 ...
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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,...
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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 =...
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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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Difference between MEAN.js and MEAN.io

...response! – CMPSoares Apr 22 '14 at 0:08 7 ...
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How do write IF ELSE statement in a MySQL query

... 150 You probably want to use a CASE expression. They look like this: SELECT col1, col2, (case when...