How to connect points with given coordinates

i have two sets of coordinates of given points and i was wandering if its possibile to plot them and to connect them with a line. so I basically have a matrix composed by 4 columns. In the first two there are the coordinates (x,y) of the first point and in the other two the coordinates of the other point, is it possible to plot them and connect the point from the first two columns to the point of the last two?

Answer 1

[Adam Danz]

Example data

mat = [1 1 11 10; 2 1 12 10; 3 1 13 10; 4 1 14 10; 5 1 15 10]
mat =
     1     1    11    10
     2     1    12    10
     3     1    13    10
     4     1    14    10
     5     1    15    10
     
     

Solution

     plot(mat(:,[1,3]), mat(:,[2,4]), 'o-')

[Adam Danz]

"In this way point 1 (a11,a12) is connected to any other point in the comlums 3 and 4 (a23,a24...), right? is there a way to connect point 1 (a11,a12) to point 1 (a13,a14) and not to all the orher ones?

thank you very much"

I don't understand this because I don't know what 'a11', 'a12', etc means. What I think you're describing is a method of drawing one line per row of the matrix. If that's the case, the solution is below. When you use the plot function, a line will be drawn for each column of input so all you need to do is transpose the the two inputs from my original solution. Transposition is done with the tick character ( ' );

plot(mat(:,[1,3])', mat(:,[2,4])', 'o-')

[emma glavich]

sorry if you didn't understand what I wrote, what I was trying to say is that, considering your matrix

mat = [1 1 11 10; 2 1 12 10; 3 1 13 10; 4 1 14 10; 5 1 15 10]
mat =
     1     1    11    10
     2     1    12    10
     3     1    13    10
     4     1    14    10
     5     1    15    10

the point (1 1) has to be linked only to the point (11 10)

the point (2 1) has to be linked only to the point (12 10)

and so on..

thank you very much for your help!

[Adam Danz]

That's what I thought. So, the solution in my comment above that uses the tranpose ( ' ) should work.

[emma glavich]

These are the two results (the first one using ('), the second one not using it), I don't know why nothing changes at all..

[Adam Danz]

That shouldn't be the case.

First check that your data are organized in the same format as you described. You should have a matrix of 4 columns. Column 1 are the (x1) coordinates, column 2 are the (y1) coordinates, col 3 are the (x2) coordinates, and col 4 are the (y2) coordinates.

Second, check that you're properly setting up the plot:

plot(mat(:,[1,3])', mat(:,[2,4])', 'o-')

If you've checked these two items and you're certain they are correct but the plot still doesn't work, attach a subsection of the first 4-5 rows of your data and share the section of code that plots that data.

Since you have so many lines, check your plot by only plotting a few of the lines and check if those lines are correctly connecting the endpoints you expect them to connect. It could be the case that your code works but there's too many lines to see what's going on.

[emma glavich]

Thank you very much for your time, you have been very kind!

Answer 2

[emma glavich]

In this way point 1 (a11,a12) is connected to any other point in the comlums 3 and 4 (a23,a24...), right? is there a way to connect point 1 (a11,a12) to point 1 (a13,a14) and not to all the orher ones?

thank you very much

[Adam Danz]

I replied in the comment section above since this is not an answer.