Draw a polygon from line equation

  • Context: MATLAB 
  • Thread starter Thread starter minhduc515
  • Start date Start date
  • Tags Tags
    Line Polygon
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
8 replies · 3K views
minhduc515
Messages
9
Reaction score
1
I'm trying to draw a quadrilateral in matlab. I has 4 line equations.
Can i draw that polygon, using line equations ? I knew MATLAB can draw polygon from coordinates, but i don't want to use it.
 
Physics news on Phys.org
You're saying that you want to draw a quadrilateral, and you have the equations of the four sides. Then just plot those lines, and they should intersect to give you the quadrilateral. Use the plot or fplot functions to plot the lines. Remember to use hold on between drawing the graphs.
 
Yes, i tried, but i don't want to have leftovers between two lines
 
minhduc515 said:
Yes, i tried, but i don't want to have leftovers between two lines
Are you saying that you don't want the sides be extended? In that case, you'll have to solve two equations at a time and find the coordinates of the four vertices. Then draw the lines from one vertex to the other, i.e. range ##x## from one vertex to the other, find ##y## for intermediate points, and plot.If you give the four equations, I can help you start.
 
  • Like
Likes   Reactions: minhduc515
This is my polygon. a,b,Z are constants
I think it's hard to find intersect between lines, so it's the reason why i don't want using coordinates to plot
240772
 
minhduc515 said:
This is my polygon. a,b,Z are constants
I think it's hard to find intersect between lines, so it's the reason why i don't want using coordinates to plot
Two small questions: 1. One axis is X, the other is y or R? 2. Is everything other than x and you a constant (including z)?
 
  • Like
Likes   Reactions: minhduc515
1. One axis is X, the other is R
2. Z, b and a are constant
 
  • Like
Likes   Reactions: Wrichik Basu
Orodruin said:
Finding the intersection between two lines is just a matter of solving a trivial linear system ...
And it can be done using solve function.

To the OP: that's what you have to do. I can't connect to MATLAB currently from my phone (I have poor network), so I cannot try at this moment. Your variables are ##x## and ##R##. Use the above function to solve the equations.
 
  • Like
Likes   Reactions: minhduc515