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How to test multiple variables against a value?
...ying to make a function that will compare multiple variables to an integer and output a string of three letters. I was wondering if there was a way to translate this into Python. So say:
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Why are these constructs using pre and post-increment undefined behavior?
... can't predict the behavior when the code is run.
As far as I know, the standard doesn't explicitly say why the concept of undefined behavior exists. In my mind, it's simply because the language designers wanted there to be some leeway in the semantics, instead of i.e. requiring that all implementa...
Reference: mod_rewrite, URL rewriting and “pretty links” explained
...plained. mod_rewrite is one way to make "pretty links", but it's complex and its syntax is very terse, hard to grok, and the documentation assumes a certain level of proficiency in HTTP. Can someone explain in simple terms how "pretty links" work and how mod_rewrite can be used to create them?
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Way to get number of digits in an int?
...thematically, numbers don't have a length, nor do they have digits. Length and digits are both properties of a physical representation of a number in a specific base, i.e. a String.
A logarithm-based solution does (some of) the same things the String-based one does internally, and probably does so ...
How do you set, clear, and toggle a single bit?
How do you set, clear, and toggle a bit?
30 Answers
30
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ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...ch was causing all sorts of problems. I was inadvertently doing a bitwise AND instead of a logical AND .
6 Answers
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What's the difference between echo, print, and print_r in PHP?
I use echo and print_r much, and almost never use print .
11 Answers
11
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How to output only captured groups with sed?
...as well as specifying what you do want.
string='This is a sample 123 text and some 987 numbers'
echo "$string" | sed -rn 's/[^[:digit:]]*([[:digit:]]+)[^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p'
This says:
don't default to printing each line (-n)
exclude zero or more non-digits
include on...
What's the difference between tilde(~) and caret(^) in package.json?
After I upgraded to latest stable node and npm , I tried npm install moment --save . It saves the entry in the package.json with the caret ^ prefix. Previously, it was a tilde ~ prefix.
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What does “dereferencing” a pointer mean?
...ring to the second byte in the process's memory, 2 the third, 3 the fourth and so on....
What happened to 0 and the first byte? Well, we'll get to that later - see null pointers below.
For a more accurate definition of what pointers store, and how memory and addresses relate, see "More about memo...