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How are the points in CSS specificity calculated
... algorithm is 256 or 28.
What this means is that a style specified with 0 ids and 256 class-names will over-ride a style specified with just 1 id. I tested this out with some fiddles:
255 classes are not enough to override 1 id
...but 256 classes are enough to override 1 id
...and 256 tag-name...
What is Bit Masking?
...
250
A mask defines which bits you want to keep, and which bits you want to clear.
Masking is the ac...
Remove outline from select box in FF
...he color of the dotted border. So say if you do...
select {
color: rgba(0,0,0,0);
}
Firefox will render the dotted border transparent. But of course your text will be transparent too! So we must somehow display the text. text-shadow comes to the rescue:
select {
color: rgba(0,0,0,0);
text-...
How to avoid reinstalling packages when building Docker image for Python projects?
...ree
.
├── Dockerfile
├── requirements.txt
└── run.py
0 directories, 3 file
# Dockerfile
FROM dockerfile/python
WORKDIR /srv
ADD ./requirements.txt /srv/requirements.txt
RUN pip install -r requirements.txt
ADD . /srv
CMD python /srv/run.py
# requirements.txt
pytest==2.3.4
# ...
How do I base64 encode (decode) in C?
...
106
Here's the one I'm using:
#include <stdint.h>
#include <stdlib.h>
static char en...
How do I convert a TimeSpan to a formatted string? [duplicate]
...
|
edited Aug 16 '09 at 17:51
answered May 8 '09 at 22:22
...
How to detect a Christmas Tree? [closed]
...
10 Answers
10
Active
...
How to validate an email address using a regular expression?
...
+50
The fully RFC 822 compliant regex is inefficient and obscure because of its length. Fortunately, RFC 822 was superseded twice and the...
How do you round a floating point number in Perl?
... and floor()?
Trig functions?
Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implement...
Add a common Legend for combined ggplots
...
108
Update 2015-Feb
See Steven's answer below
df1 <- read.table(text="group x y
gro...