Plot a nx2 matrix as points

Hello, I have different nx2 matrices as outputs from earhquake signals, where n can vary. I would like to plot these matrices as points where n is the number of points and the first and second columns contain the x and y value for each point. Let us say I have a matrix A as follow:

A[0.5 2; 1.0 -0.8; 1.5 -2.5]

Herein, (0.5,2), (1.0, -0.8), and (1.5, -2.5) would the coordinates of the points I would like to plot. Thank you for your response.

Answer 1

[Torsten]

A=[0.5 2; 1.0 -0.8; 1.5 -2.5];
plot(A(:,1),A(:,2),'o')

[Dyuman Joshi]

One can also use scatter -

A = [0.5 2; 1.0 -0.8; 1.5 -2.5];
scatter(A(:,1),A(:,2),'r*')
axis('equal')

[Jorge Luis Paredes Estacio]

Thank you

Answer 2

[Pranavkumar Mallela]

Hi Jorge,

I understand that you want to plot the points obtained from a given nx2 matrix.

It can be done by extracting the x, y coordinates using array indexing. The graph can be plotted using the 'plot' function. Using '-*' in the 'plot' function will help you see the points.

Please find the code below:

A = [0.5 2; 1.0 -0.8; 1.5 -2.5]

A = 3×2

0.5000 2.0000 1.0000 -0.8000 1.5000 -2.5000

x = A(:,1)

x = 3×1

0.5000 1.0000 1.5000

y = A(:,2)

y = 3×1

2.0000 -0.8000 -2.5000

plot(x, y, '-*')

For more information regarding extracting points, please refer the following documentation: https://www.mathworks.com/help/matlab/math/array-indexing.html

For more information regarding the 'plot' function, please refer the following documentation: https://www.mathworks.com/help/matlab/ref/plot.html

Hope this helps! Thanks!

[Jorge Luis Paredes Estacio]

Hi. Thank you for your answer. However, I do not want to plot a line, I just want to plot them as shaded points on top another plot that contains the earthquake signal as lines.