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What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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pyplot scatter plot marker size
...This can be a somewhat confusing way of defining the size but you are basically specifying the area of the marker. This means, to double the width (or height) of the marker you need to increase s by a factor of 4. [because A = WH => (2W)(2H)=4A]
There is a reason, however, that the size of mark...
How to check for file lock? [duplicate]
...ld become locked the very next second (read: short timespan).
Why specifically do you need to know if the file is locked anyway? Knowing that might give us some other way of giving you good advice.
If your code would look like this:
if not locked then
open and update file
Then between the t...
How can I increment a char?
...and C. How can I increment a char? In Java or C, chars and ints are practically interchangeable, and in certain loops, it's very useful to me to be able to do increment chars, and index arrays by chars.
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How to recognize USB devices in Virtualbox running on a Linux host? [closed]
...and log in again
Attach to your PC the USB devices you want to be automatically mounted in the VM (virtual machine).
Open Virtualbox
Select your VM and go to "Machine" -> "Settings" -> "USB".
Check "Enable USB Controller"; click on the icon with the USB plug and the plus, and
click on the devi...
Remove an Existing File from a Git Repo
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Just to give the full answer all at once:
from klemens: You need to add the file to your .gitignore file somewhere above the undesired file in the repo. i.e.
$ cd
$ cat >> .gitignore
development.log
C-d
from m. narebski: You then need to remove...
How to detect a textbox's content has changed
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The only downfall of 'input' is that it is not compatible with IE < 9.
– Catfish
Mar 21 '13 at 20:02
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Reset CSS display property to default value
... value, not the browser default. The spec itself makes this note under the all property:
For example, if an author specifies all: initial on an element it will block all inheritance and reset all properties, as if no rules appeared in the author, user, or user-agent levels of the cascade.
This can ...
Application Skeleton to support multiple screens
...d Screen-size so while developing an Application which support
multiple (small and big) screen there is an obstacle of size and layout.
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Regex for splitting a string using space when not surrounded by single or double quotes
...ing to put together an expression that will split the example string using all spaces that are not surrounded by single or double quotes. My last attempt looks like this: (?!") and isn't quite working. It's splitting on the space before the quote.
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