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When to use PNG or JPG in iPhone development?
...more compressed image formats, and thus be slower to display.
JPG's are smaller to store, but lossy (amount depends on compression level), and to display them requires a much more complicated decoding algorithm. But the typical compression and image quality is usually quite sufficient for photos.
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Getting started with Haskell
...'ve done this by reading tutorials and watching screencasts, but nothing really seems to stick.
Now, in learning various imperative/OO languages (like C, Java, PHP), exercises have been a good way for me to go. But since I don't really know what Haskell is capable of and because there are many new c...
Something like 'contains any' for Java set?
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Actually it will short-circuit as soon as it finds the first common element
– Xipo
Dec 15 '16 at 10:54
3
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Git: How to rebase to a specific commit?
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For me, this doesn't actually do what's intended. As far as I can tell, it tries to rebase onto the "last common ancestor" of topic and commitB.
– Dan Lenski
Jan 26 '15 at 18:20
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Linux delete file with size 0 [duplicate]
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This will delete all the files in a directory (and below) that are size zero.
find /tmp -size 0 -print -delete
If you just want a particular file;
if [ ! -s /tmp/foo ] ; then
rm /tmp/foo
fi
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What is a “slug” in Django?
When I read Django code I often see in models what is called a "slug". I am not quite sure what this is, but I do know it has something to do with URLs. How and when is this slug-thing supposed to be used?
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What are the lesser known but useful data structures?
There are some data structures around that are really useful but are unknown to most programmers. Which ones are they?
83 A...
Is it possible to “decompile” a Windows .exe? Or at least view the Assembly?
...ious to see what it does without infecting myself. I know that you can't really decompile an .exe, but can I at least view it in Assembly or attach a debugger?
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e to go with @Moody_Mudskipper's answer: Using .drop=FALSE can give potentially unexpected results when one or more grouping variables are not coded as factors. See examples below:
library(dplyr)
data(iris)
# Add an additional level to Species
iris$Species = factor(iris$Species, levels=c(levels(ir...
Boolean operators && and ||
...es the longer form "appropriate for programming control-flow and [is] typically preferred in if clauses."
So you want to use the long forms only when you are certain the vectors are length one.
You should be absolutely certain your vectors are only length 1, such as in cases where they are funct...