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How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
...way to go (as opposed to articles like this)? I see you're trying to vertically center the element, so why do you have to set margin-top:-8px; and not margin-top:-50%;?
Well, vertical centering in CSS is harder than it should be. When setting even top or bottom margins in %, the value is calculated...
Passing arrays as parameters in bash
...eing defined with local, because locals are visible to the functions they call.
The ! in ${!1} expands the arg 1 variable.
declare -a just makes the indexed array explicit, it is not strictly necessary.
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Rails: Default sort order for a rails model?
...ow use Book.published.confirmed.
With this method, the query is not actually executed until actual results are needed (lazy evaluation), so 7 scopes could be chained together but only resulting in 1 actual database query, to avoid performance problems from executing 7 separate queries.
You can u...
Add a “hook” to all AJAX requests on a page
...ttle investigating and this is what I came up with.
I'm not sure that it's all that useful as per the comments in the script and of course will only work for browsers using a native XMLHttpRequest object.
I think it will work if javascript libraries are in use as they will use the native object if p...
Automatic prune with Git fetch or pull
... work is over and I don't know, I won't do a git fetch --prune and eventually I will push back the deleted branch.
3 Answ...
Child with max-height: 100% overflows parent
... child's max-height to be calculated from, so max-height computes to none, allowing the child to be as tall as possible. The only other constraint acting on the child now is the max-width of its parent, and since the image itself is taller than it is wide, it overflows the container's height downwar...
Why is there huge performance hit in 2048x2048 versus 2047x2047 array multiplication?
...he misses on matice1 are not the problem because they are accessed sequentially.
However for matice2 if a full column fits in L2 (i.e when you access matice2[0, 0], matice2[1, 0], matice2[2, 0] ... etc, nothing gets evicted) than there is no problem with cache misses with matice2 either.
Now to go ...
Remove duplicated rows using dplyr
... @hadley I like the unique() and distinct() function, however, they all remove the 2nd duplicate from the data frame. what if I want to have all 1st encounters of the duplicate value removed? How could this be done? Thanks for any help!
– FlyingDutch
Feb...
Why doesn't Java offer operator overloading?
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It's pretty simple really... Just do like Python and have no overloaded assignment.
– L̲̳o̲̳̳n̲̳̳g̲̳̳p̲̳o̲̳̳k̲̳̳e̲̳̳
Jun 5 '10 at 14:32
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How to make the first option of selected with jQuery
...l($("#target option:first").val()); will work in IE6, because you are literally looking up the first value, and entering it as target's value. Two id lookups instead of one.
– Nicholi
Feb 4 '12 at 1:56
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