Communities

Writing
Writing
Codidact Meta
Codidact Meta
The Great Outdoors
The Great Outdoors
Photography & Video
Photography & Video
Scientific Speculation
Scientific Speculation
Cooking
Cooking
Electrical Engineering
Electrical Engineering
Judaism
Judaism
Languages & Linguistics
Languages & Linguistics
Software Development
Software Development
Mathematics
Mathematics
Christianity
Christianity
Code Golf
Code Golf
Music
Music
Physics
Physics
Linux Systems
Linux Systems
Power Users
Power Users
Tabletop RPGs
Tabletop RPGs
Community Proposals
Community Proposals
tag:snake search within a tag
answers:0 unanswered questions
user:xxxx search by author id
score:0.5 posts with 0.5+ score
"snake oil" exact phrase
votes:4 posts with 4+ votes
created:<1w created < 1 week ago
post_type:xxxx type of post
Search help
Notifications
Mark all as read See all your notifications »
Q&A

Welcome to the Power Users community on Codidact!

Power Users is a Q&A site for questions about the usage of computer software and hardware. We are still a small site and would like to grow, so please consider joining our community. We are looking forward to your questions and answers; they are the building blocks of a repository of knowledge we are building together.

How to add vertical line in the middle of two marks on image

+1
−0

Have

This .png image of a plot: Busy Bar Graph

Want

To add vertcal lines between the groupings:
(0, 1, 2) LINE (3, 4, 5) LINE (6, 7, 8)

I want to place the lines exactly in the middle of the grouping boundaries.

The solution I envision is marking (*) the vertical edges of the bars of each grouping boundary, and then placing a line exactly between those two marks:
(0, 1, 2)* LINE *(3, 4, 5)...

Notes

I am using Linux, and have access to Gimp. That being said, I am open to better suited software other than Gimp, as long as it's available for Linux.

Inspired by this post.

History
Why does this post require moderator attention?
You might want to add some details to your flag.
Why should this post be closed?

1 comment thread

How was that image generated, and what is the desired final outcome? (4 comments)

1 answer

+1
−0

If you have access to the source of the image, fix the code instead of messing with the image. This will be much more accurate and result in a higher quality result.


You could add the lines via latex (texlive is available via the usual linux package managers, but is often already installed because many other tools have it as dependency).

  1. first determined the coordinates of the 0 and 8 x ticks (the commented green help lines in the example below). I'm using these coordinates instead of trying to determine the location of the bars, because these span a larger interval and thus the error from doing this by eye will be smaller. In the example below, they are at -16.1 and 17.45.

  2. next calculate from these coordinates the location of your desired lines, -5.6158 and 6.9653.

(might be a bit overkill, but I think this will ensure that the lines are placed as precisely as possible)

\documentclass{standalone}
\usepackage{tikz}

\begin{document}
	
\begin{tikzpicture}[inner sep=0pt,outer sep=0pt]
\node at (0,0) {\includegraphics{ULaNwNrkXuSqPYiKGbEjrzGa}};
%\draw[green,line width=5pt] (-16.1,-10.1) -- ++(0,19.9);
%\draw[green,line width=5pt] (17.45,-10.1) -- ++(0,19.9);

\draw[magenta,line width=5pt] (-5.6158,-10.1) -- ++(0,19.9);
\draw[magenta,line width=5pt] (6.9653,-10.1) -- ++(0,19.9);
\end{tikzpicture}	
	
\end{document}

(replace ULaNwNrkXuSqPYiKGbEjrzGa with the filename of your image)

plot with added vertical lines

History
Why does this post require moderator attention?
You might want to add some details to your flag.

1 comment thread

@#36377 this is a very clever solution. How did you figure out the coordinates? Was it trial and erro... (2 comments)

Sign up to answer this question »