Plot over a image

15 次查看(过去 30 天)
Vittorio Faustinella
Hello to all,
I've a question, i want plot a graphic over a image, I've write this code:
%Plot Sw - r^2/t
figure(1)
imshow('Image2011.jpg'),colormap jet
hold on
semilogx(s.Sim,s.S_w, 'k');
xlabel r^2/t(m^2/s)
ylabel Sw
xlim([0.0001, 1])
ylim([0,1])
hold off
but it doesn't work because the two graphs do not coincide. How can I do?
This is the image:

回答(1 个)

Walter Roberson
Walter Roberson 2021-12-4
%Plot Sw - r^2/t
figure(1)
Image2011 = imread('Image2011.jpg');
image([0 1], [0 1], Image2011)
colormap jet
hold on
semilogx(s.Sim,s.S_w, 'k');
xlabel r^2/t(m^2/s)
ylabel Sw
xlim([0.0001, 1])
ylim([0,1])
hold off
Note that jpg images are almost always RGB images, so the colormap jet is probably not going to affect the display of the image. It might as there are some grayscale JPG images... they are just very very uncommon, with it being much more common that what looks like a grayscale JPG image is really an RGB image.
  5 个评论
Walter Roberson
Walter Roberson 2021-12-5
Hmmmm, there is a bit of a difficulty there. The plot in the image is in log scale, but you cannot use log scale with negative coordinates.
So you have two choices:
  1. Use two different axes with one overlaying the other, one with linear scale used to hold the image, and the other with log scale positioned a little to the right of the start of the other axes so that the 0.000001 point aligns with the image left hand side; OR
  2. use a single linear scale, but do a log transform of the x coordinates to determine linear coordinates to draw the data at; in such a case the image should probably be placed to have an x limit of 6
Vittorio Faustinella
Thank you for your time, I'll figure it out.

请先登录,再进行评论。

类别

Help CenterFile Exchange 中查找有关 Visual Exploration 的更多信息

产品


版本

R2019b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by