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Geometric Mean: is there a built-in?
...na.rm=TRUE){
exp(sum(log(x[x > 0]), na.rm=na.rm) / length(x))
}
Thanks to @ben-bolker for noting the na.rm pass-through and @Gregor for making sure it works correctly.
I think some of the comments are related to a false-equivalency of NA values in the data and zeros. In the application I had...
Best way of returning a random boolean value
...sing this for some time to return either true or false when building fake seed data. Just wondering if anybody has a better, more succinct or verbose way of returning either true or false .
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Best practices for in-app database migration for Sqlite
...and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing with this variable, you are free to use it however you please). It starts at 0, and you can get/set this variable ...
Insert new item in array on any position in PHP
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jay.leejay.lee
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How to prevent IFRAME from redirecting top-level window
Some websites have code to "break out" of IFRAME enclosures, meaning that if a page A is loaded as an IFRAME inside an parent page P some Javascript in A redirects the outer window to A .
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How can I position my div at the bottom of its container?
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Likely not.
Assign position:relative to #container, and then position:absolute; bottom:0; to #copyright.
#container {
position: relative;
}
#copyright {
position: absolute;
bottom: 0;
}
<div id="co...
SQLite UPSERT / UPDATE OR INSERT
...do have the option to upgrade, you are strongly encouraged to do so as unlike my solution, the one posted here achieves the desired behavior in a single statement. Plus you get all the other features, improvements and bug fixes that usually come with a more recent release.
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View HTTP headers in Google Chrome?
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I'm not sure about your exact version, but Chrome has a tab "Network" with several items and when I click on them I can see the headers on the right in a tab.
Press F12 on windows or ⌥⌘I on a mac to bring up the Chrome developer tools.
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Standardize data columns in R
...rnorm(10, 30, .2), y = runif(10, 3, 5))
scaled.dat <- scale(dat)
# check that we get mean of 0 and sd of 1
colMeans(scaled.dat) # faster version of apply(scaled.dat, 2, mean)
apply(scaled.dat, 2, sd)
Using built in functions is classy. Like this cat:
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What's in an Eclipse .classpath/.project file?
...ent Eclipse view. What's the project's name? what other projects in the workspace does it refer to? What are the builders that are used in order to build the project? (remember, the concept of "build" doesn't pertain specifically to Java projects, but also to other types of projects)
The .classpath...