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How do you plot bar charts in gnuplot?
... boxes
data.dat:
0 label 100
1 label2 450
2 "bar label" 75
If you want to style your bars differently, you can do something like:
set style line 1 lc rgb "red"
set style line 2 lc rgb "blue"
set style fill solid
set boxwidth 0.5
plot "data.dat" every ::0::0 using 1:3:xtic(2) wit...
What does “default” mean after a class' function declaration?
... the compiler-generated version of that function, so you don't need to specify a body.
You can also use = delete to specify that you don't want the compiler to generate that function automatically.
With the introduction of move constructors and move assignment operators, the rules for when automat...
Returning value from called function in a shell script
...options:
1. Echo strings
lockdir="somedir"
testlock(){
retval=""
if mkdir "$lockdir"
then # Directory did not exist, but it was created successfully
echo >&2 "successfully acquired lock: $lockdir"
retval="true"
else
echo >&2 "cannot acquire ...
How do I get the full path of the current file's directory?
... script being run:
import os
os.path.dirname(os.path.abspath(__file__))
If you mean the current working directory:
import os
os.path.abspath(os.getcwd())
Note that before and after file is two underscores, not just one.
Also note that if you are running interactively or have loaded code from...
Is there a Python equivalent of the C# null-coalescing operator?
...
other = s or "some default value"
Ok, it must be clarified how the or operator works. It is a boolean operator, so it works in a boolean context. If the values are not boolean, they are converted to boolean for the purposes of the operator.
Note that the or operator does not r...
PostgreSQL create table if not exists
...
This feature has been implemented in Postgres 9.1:
CREATE TABLE IF NOT EXISTS myschema.mytable (i integer);
For older versions, here is a function to work around it:
CREATE OR REPLACE FUNCTION create_mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT FROM ...
Best way to add “current” class to nav in Rails 3
...on?(*action)
action.include?(params[:action])
end
Then you can use if controller?("homepage") && action?("index", "show") in your views or other helper methods…
share
|
improve thi...
Appropriate datatype for holding percent values?
..., the data type you use depends on how you plan to store your percentages. If you are going to store their fractional equivalent (e.g. 100.00% stored as 1.0000), I would store the data in a decimal(5,4) data type with a CHECK constraint that ensures that the values never exceed 1.0000 (assuming that...
jQuery: Check if div with certain class name exists
...
You can simplify this by checking the first object that is returned from JQuery like so:
if ($(".mydivclass")[0]){
// Do something if class exists
} else {
// Do something if class does not exist
}
In this case if there is a tr...
Delete commits from a branch in Git
...back up to, and then do this:
git reset --hard <sha1-commit-id>
If you already pushed it, you will need to do a force push to get rid of it...
git push origin HEAD --force
However, if others may have pulled it, then you would be better off starting a new branch. Because when they pull...