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How to count TRUE values in a logical vector
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Another option which hasn't been mentioned is to use which:
length(which(z))
Just to actually provide some context on the "which is faster question", it's always easiest just to test yourself. I made the vector much larger for comparison:
z <- sample(c(TR...
What's the difference between window.location= and window.location.replace()?
...he provided URL.
replace(url):Replace the current
document with the one at the provided
URL. The difference from the
assign() method is that after using
replace() the current page will not
be saved in session history, meaning
the user won't be able to use the Back
button to naviga...
Add centered text to the middle of a -like line
I'm wondering what options one has in xhtml 1.0 strict to create a line on both sides of text like-so:
32 Answers
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How can I parse a YAML file from a Linux shell script?
...d to pull in some YAML as bash variables. The YAML will never be more than one level deep.
YAML looks like so:
KEY: value
ANOTHER_KEY: another_value
OH_MY_SO_MANY_KEYS: yet_another_value
LAST_KEY: last_value
Output like-a dis:
KEY="value"
ANOTHER_KEY="another_val...
How to “git show” a merge commit with combined diff output even when every changed file agrees with
After doing a "simple" merge (one without conflicts), git show usually only shows something like
11 Answers
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How to wait for several Futures?
... but the issue comes from knowing which Future to remove from the Map when one has been successfully completed. As long as you have some way to properly correlate a result with the Future that spawned that result, then something like this works. It just recursively keeps removing completed Futures...
How to get box-shadow on left & right sides only
... solution described here.
You can get close with multiple box-shadows; one for each side
box-shadow: 12px 0 15px -4px rgba(31, 73, 125, 0.8), -12px 0 8px -4px rgba(31, 73, 125, 0.8);
http://jsfiddle.net/YJDdp/
Edit
Add 2 more box-shadows for the top and bottom up front to mask out the that ...
Focus-follows-mouse (plus auto-raise) on Mac OS X
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That makes a lot of sense. One thing that annoys/confuses me is that the scroll behavior does seem to have a lazy focus. So I can move the mouse over to another window, scroll the text, and then when I start typing, the output goes to another applicat...
Throw an error in a MySQL trigger
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Here is one hack that may work. It isn't clean, but it looks like it might work:
Essentially, you just try to update a column that doesn't exist.
share
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What is an example of the Liskov Substitution Principle?
...o a Square, then SetWidth and SetHeight doesn't make sense because setting one would change the other to match it. In this case Square fails the Liskov Substitution Test with Rectangle and the abstraction of having Square inherit from Rectangle is a bad one.
Y'all should check out the other price...