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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...swer your question directly, but it will give you the elements that are in common. This can be done with Paul Murrell's package compare:
library(compare)
a1 <- data.frame(a = 1:5, b = letters[1:5])
a2 <- data.frame(a = 1:3, b = letters[1:3])
comparison <- compare(a1,a2,allowAll=TRUE)
compa...
PHP foreach change original array values
...
In PHP, passing by reference (&) is ... controversial. I recommend not using it unless you know why you need it and test the results.
I would recommend doing the following:
foreach ($fields as $key => $field) {
if ($field['required'] && strlen($_POST[$field['name']])...
Does static constexpr variable inside a function make sense?
...atic and constexpr ? constexpr guarantees that the array is created at compile time, so would the static be useless?
...
source of historical stock data [closed]
... to start with a "discount" data feed will do, but as soon as you run more comprehensive backtests you might run into problems depending on what you do. If you just look at, let's say, the S&P 500 stocks this will not be so much a problem though and a "cheap" intraday feed will do.
What you wi...
Brew doctor says: “Warning: /usr/local/include isn't writable.”
... it and everything in it.
Mac OS High Sierra or newer: (ty to Kirk in the comments below)
$ sudo chown -R $(whoami) $(brew --prefix)/*
Previous versions of macos:
$ sudo chown -R $USER:admin /usr/local/include
Then do another
$ brew doctor
...
Calling shell functions with xargs
I am trying to use xargs to call a more complex function in parallel.
5 Answers
5
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Is there a way to break a list into columns?
...
It works "everywhere" except Internet Explorer 9 or older: http://caniuse.com/multicolumn
ul {
-moz-column-count: 4;
-moz-column-gap: 20px;
-webkit-column-count: 4;
-webkit-column-gap: 20px;
column-count: 4;
column-gap: 20px;
}
See: http://jsfiddle.net/pdExf/
If IE suppo...
How do I clone a subdirectory only of a Git repository?
...parse fetch" on the git mailinglist.
In general, the consensus in the Git community is that if you have several directories that are always checked out independently, then these are really two different projects and should live in two different repositories. You can glue them back together using Gi...
What C++ Smart Pointer Implementations are available?
...ection thread where what I thought was a simple answer generated a lot of comments about some specific smart pointer implementations so it seemed worth starting a new post.
...
Edit the root commit in Git?
There's ways to change the message from later commits:
5 Answers
5
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