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What is the difference between id and class in CSS, and when should I use them? [duplicate]
Here I gave an id to the div element and it's applying the relevant CSS for it.
15 Answers
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Geometric Mean: is there a built-in?
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Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...
How to create nonexistent subdirectories recursively using Bash?
... script that will dump some databases into a nice/neat directory structure and I realized that I need to test to make sure that the directories exist before I create them. The code I have works, but it seems that there is a better way to do it. Any suggestions?
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How to upload a file in Django? [closed]
...xample about this. I spent over 2 hours to dig up all the pieces to understand how this works. With that knowledge I implemented a project that makes possible to upload files and show them as list. To download source for the project, visit https://github.com/axelpale/minimal-django-file-upload-exam...
How to use JavaScript regex over multiple lines?
...to match all newlines, you would need to add \r as well to include Windows and classic Mac OS style line endings: (.|[\r\n]).
That turns out to be somewhat cumbersome, as well as slow, (see KrisWebDev's answer for details), so a better approach would be to match all whitespace characters and all no...
Bash: Syntax error: redirection unexpected
...solved:
The exec form makes it possible to avoid shell string munging, and
to RUN commands using a base image that does not contain /bin/sh.
Note
To use a different shell, other than /bin/sh, use the exec form
passing in the desired shell. For example,
RUN ["/bin/bash", "-c", "ec...
Place a button right aligned
...from the normal document flow so they can overflow their parent's boundary and mess up the parent's height, the clear:both CSS takes care of that (as does overflow:hidden). Play around with the JSFiddle example I added to see how floating and clearing behave (you'll want to drop the overflow:hidden ...
Cross-browser multi-line text overflow with ellipsis appended within a fixed width and height
I made an image for this question to make it easier to understand.
25 Answers
25
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JavaScript + Unicode regexes
...egex. See Unicode-aware regular expressions in ES6.
Until ES 6 is finished and widely adopted among browser vendors you're still on your own, though. Update: There is now a transpiler named regexpu that translates ES6 Unicode regular expressions into equivalent ES5. It can be used as part of your bu...
How to vertically center a container in Bootstrap?
... for a way to vertically center the container div inside the jumbotron and to set it in the middle of the page.
9 Answ...