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Curly braces in string in PHP
...echo "This is ${great}";
// Works
echo "This square is {$square->width}00 centimeters broad.";
// Works, quoted keys only work using the curly brace syntax
echo "This works: {$arr['key']}";
// Works
echo "This works: {$arr[4][3]}";
// This is wrong for the same reason as $foo[bar] is wrong...
How to add texture to fill colors in ggplot2
... Claus Wilke
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answered Jun 10 '10 at 1:08
AndreasAndreas
5,8841010 gold ba...
Confusion between factor levels and factor labels
...ends?
– donodarazao
May 3 '11 at 13:02
6
I would often transform the levels right before plotting...
Checking for NULL pointer in C/C++ [closed]
...
206
In my experience, tests of the form if (ptr) or if (!ptr) are preferred. They do not depend on ...
List comprehension vs map
... map when using exactly the same function:
$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely r...
Compare integer in bash, unary operator expected
... specifying a default value for $i if $i is blank, as follows:
if [ "${i:-0}" -ge 2 ] ; then ...
This will substitute the value 0 instead of $i is $i is undefined. I still maintain the quotes because, again, if $i is a bunch of blanks then it does not count as undefined, it will not be replaced ...
Symbol for any number of any characters in regex?
...ace or any non-whitespace) as many times as possible down to and including 0.
[\s\S]*
This expression will match as few as possible, but as many as necessary for the rest of the expression.
[\s\S]*?
For example, in this regex [\s\S]*?B will match aB in aBaaaaB. But in this regex [\s\S]*B will...
CSS: transition opacity on mouse-out?
...
202
You're applying transitions only to the :hover pseudo-class, and not to the element itself.
.i...
Check if a number has a decimal place/is a whole number
...
20 Answers
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Check variable equality against a list of values
...
GumboGumbo
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