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Unix shell script to truncate a large file
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: > filename
: is a no-op in bash (POSIX-compliant), so this essentially just opens the file for writing (which of course truncates the file) and then immediately closes it.
EDIT: as shellter commented, you don't actually need a command to go along with the redirection:
$ echo foo > foo....
Why is there a `null` value in JavaScript?
In JavaScript, there are two values which basically say 'I don't exist' - undefined and null .
12 Answers
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What rules does Pandas use to generate a view vs a copy?
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Here's the rules, subsequent override:
All operations generate a copy
If inplace=True is provided, it will modify in-place; only some operations support this
An indexer that sets, e.g. .loc/.iloc/.iat/.at will set inplace.
An indexer that gets on a single-dtyped o...
Can I embed a custom font in an iPhone application?
...plist, you can use your custom fonts as any other font in IB or programatically.
There is an ongoing thread on Apple Developer Forums:
https://devforums.apple.com/thread/37824 (login required)
And here's an excellent and simple 3 steps tutorial on how to achieve this (broken link removed)
Add y...
Why does C# disallow readonly local variables?
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It actually has nothing to do with CLI support for the feature, because local variables are in no way exposed to other assemblies. The readonly keyword for fields needs to be supported by the CLI because its effect is visible to oth...
Storing Objects in HTML5 localStorage
... can even store an array of objects if you want.
– zuallauz
Aug 16 '11 at 21:38
8
It is just bool...
data.frame rows to a list
...ts in your list are atomic vectors, not list as the OP requested. It is usually not a problem until your xy.df contains mixed types...
– Calimo
Feb 28 '14 at 14:40
2
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Batch file to copy directories recursively
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There are examples, 2/3 down the page. Of particular use is:
To copy all the files and subdirectories (including any empty subdirectories) from drive A to drive B, type:
xcopy a: b: /s /e
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Assert equals between 2 Lists in Junit
...t(actual, is(not(expected)));
}
If you have a recent version of Junit installed with hamcrest, just add these imports:
import static org.junit.Assert.*;
import static org.hamcrest.CoreMatchers.*;
http://junit.org/junit4/javadoc/latest/org/junit/Assert.html#assertThat(T, org.hamcrest.Matcher)
http:...
Why use Dijkstra's Algorithm if Breadth First Search (BFS) can do the same thing faster?
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Dijkstra allows assigning distances other than 1 for each step. For example, in routing the distances (or weights) could be assigned by speed, cost, preference, etc. The algorithm then gives you the shortest path from your source to e...