How to set axis for multiple subplots of pictures in Matlab - matlab

clear all; close all; clc;
A = im2double(imread('cameraman.jpg'));
figure(1)
imshow(A)
C = chunking(A,400,400) % separates picture;
[m n] = size(C);
k = 1;
figure(1)
for i = 1:m
for j = 1:n
subplot(m,n,k)
imshow(C{i,j})
axis off;
k = k + 1;
end
end
So In the above code, I am trying to separate a picture into 400x400 pixel chunks. Since the image is not a multiple of 400x400, it will have unequal sections on the border and bottom right corner (still a square image). However, when I use subplot, it resizes the last chunk to be the same size. I tried playing around with get and set position but it gives that the width and height for each subplot is the same?![enter image description here][1]
http://imgur.com/2VUYZr1

You want to resize the axes if you have less than 400 pixels to display. You should store the handle to each subplot and then resize it if it needs to be smaller.
Your call to subplot should look like this:
h = subplot(m,n,k);
num_rows = size(C{i,j}, 1);
num_cols = size(C{i,j}, 2);
set(h, 'units', 'pixels')
old_axes_pos = get(h, 'position');
new_axes_pos = old_axes_pos;
if num_cols < 400
new_axes_pos(3) = num_cols; % Make this axes narrower
end
% If the figure cannot be full height
if num_rows < 400
new_axes_pos(4) = num_rows; % Make this axes shorter
new_axes_pos(2) = old_axes_pos(2) + (400 - num_rows); % Move the bottom up
end
set(h, 'position', new_axes_pos) % Change the size of the figure

Related

Resize axes to fit image

How can I resize my axes on a matlab GUI to fit exactly with the size of the image I just resized?
I have this:
I = imread('honolulu.png');
I = imresize(im2double(I), [600, 700]);
After that I am drawing a grid on the pictures, but because the axes size is different the grid does not look good. However, if I create a figure and I do it on a figure outside the GUI it looks perfect.
Full code:
%Load map
I = imread('honolulu.png');
%Resize image to be multiple of 50 in each axis.
I = imresize(im2double(I), [600, 700]);
%Draw grid of 50x50 pixels.
I(50:50:end, :, :) = 255;
I(:, 50:50:end, :) = 255;
axes(handles.axes1);
h = handles.axes1;imshow(I);
while (ishandle(h))
try
[x, y] = ginput(1);
catch me
%break loop in case image is closed.
break;
end
%Compute top left coordinate of block clicked.
x0 = floor((x-1)/50)*50;
y0 = floor((y-1)/50)*50;
%Set block RGB to random color.
I(y0+1:y0+50-1, x0+1:x0+50-1, 1) = rand();
I(y0+1:y0+50-1, x0+1:x0+50-1, 2) = rand();
I(y0+1:y0+50-1, x0+1:x0+50-1, 3) = rand();
imshow(I);
end
% Choose default command line output for city_planning
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
How it looks vs how it is supposed to look
The lines are disappearing as the plot window changes size - something of an aliasing/rendering issue I guess. Elsewhere other people have asked similar questions without a great answer.
The best I've found is setting the initial magnification to 100% and then preventing resizing. Here's a similar example:
close all;
clear all;
clc;
I = imread('peppers.png');
I = imresize(im2double(I), [600, 700]);
%Draw grid of 50x50 pixels.
I(50:50:end, :, :) = 1;
I(:, 50:50:end, :) = 1;
h = imshow(I,'initialMagnification',100);
set(gcf,'Resize','off')
%%
while (ishandle(h))
try
[x, y] = ginput(1);
catch me
%break loop in case image is closed.
break;
end
%Compute top left coordinate of block clicked.
x0 = floor((x-1)/50)*50;
y0 = floor((y-1)/50)*50;
%Set block RGB to random color.
I(y0+1:y0+50-1, x0+1:x0+50-1, 1) = rand();
I(y0+1:y0+50-1, x0+1:x0+50-1, 2) = rand();
I(y0+1:y0+50-1, x0+1:x0+50-1, 3) = rand();
h = imshow(I);
end

How can I add subtitle for each image below figure in matlab

I am using subplot to display multiple image in the a figure. I want to add the subtitle (a),(b),...(c) below each image as the below figure:
Could you help to write it in MATLAB? This is current code for above image. if it is possible, let me know how to control the margin between image and the sub-title. Thanks
%# read images in a cell array
imgs = cell(6,1);
for i=1:6
imgs{i} = imread( sprintf('AT3_1m4_%02d.tif',i) );
end
%# show them in subplots
figure(1)
for i=1:6
subplot(2,3,i);
h = imshow(imgs{i}, 'InitialMag',100, 'Border','tight');
title(num2str(i))
set(h, 'ButtonDownFcn',{#callback,i})
end
Updated: I also tried with subaxis lib. However, the result do not show titles
%% read images in a cell array
imgs = cell(6,1);
for i=1:6
imgs{i} = imread( sprintf('AT3_1m4_%02d.tif',i) );
end
figure(1)
spaceH=0.01;spaceV=0.1;marTop=0.3;marBot=0.0;
padding=0.0;margin=0.0;marginL=0.0;
for i=1:6
subaxis(2,3,i,'SpacingHoriz', spaceH, ...
'SpacingVert',spaceV, 'PL',padding,'PR',padding,'mt',...
marTop,'mb',marBot,'ML',marginL,'MR',margin); title('Original');
imagesc(uint8(imgs{i}),[0 255]),colormap(gray),axis off;axis equal,
xlabel(['(' char(96+1) ')']);
end
Try this. To specify a margin just set the 'margin' variable to whatever you need.
% show images with subtitles
figure(1);
margin = 0; % margin between title and image (in ex)
title_names = {'(a)','(b)','(c)','(d)','(e)','(f)'};
for i=1:6
subplot(2,3,i);
handle_image = imshow(imgs{i}, 'InitialMag',100, 'Border','tight');
handle_title = title(title_names{i});
set(handle_image, 'ButtonDownFcn',{#callback,i})
% adjust title position -- in 2 steps
% first set the title position to the bottom of the image
image_height = get(handle_image,'YData');
image_height(1) = [];
position = get(handle_title,'Position');
position(2) = image_height;
set(handle_title,'Position',position);
% then move it out of the image and apply some margin
set(handle_title,'Units','characters');
position = get(handle_title,'Position');
position(2) = position(2) - margin - 1;
set(handle_title,'Position',position);
% EDIT: this line will keep titles on their relative position
set(handle_title,'Units','normalized');
end
Note that you have to define #callback within the same namespace or it will throw an error, whenever you klick on an image.
This is an example result using 'trees.tiff' and a margin of 0.5ex.
EDIT: If you want to alter the figure size dynamicly the titles woun't adjust in x direction. To get a similar behavior then classic 'titles' add
set(handle_title,'Units','normalized');
below all other lines. This will keep the title at the same relative coordinates in the figure instead of the same fixed coordinates.
First of all, for controlling subplot margins and other properties, I highly recommend the tight_subplot function that may be found at the Mathworks File Exchange.
As for the specific question for adding labels, you can use xlabel. Example:
figure(1)
for i=1:6
subplot(2,3,i);
h = plot(1:20, randn(20,1));
xlb{i} = xlabel(['(' char(96+i) ')']);
end
You can control the location of the label by tuning the Position property of the labels, which are actually text objects. Example:
% Move all xlabels down by yoffset
yoffset = 0.3;
for ii = 1:6
xp = get(xlb{ii}, 'position');
xp(2) = xp(2) - yoffset; % update y-position
set(xlb{ii}, 'position', xp); % assign new position
end
After read solution of mikkola. I would like thank for your help. I would like to post my solution which may be helpful for other people
This is my solution
%% read images in a cell array
imgs = cell(6,1);
for i=1:6
imgs{i} = imread( sprintf('AT3_1m4_%02d.tif',i) );
end
figure(1)
spaceH=0.01;spaceV=0.06;marTop=0.3;marBot=0.08;
padding=0.0;margin=0.0;marginL=0.0;
yoffset = 12;
for i=1:6
subaxis(2,3,i,'SpacingHoriz', spaceH, ...
'SpacingVert',spaceV, 'PL',padding,'PR',padding,'mt',...
marTop,'mb',marBot,'ML',marginL,'MR',margin); title('Original');
% imagesc(uint8(imgs{i}),[0 255]),colormap(gray);axis equal,
imshow(imgs{i}, 'InitialMag',90, 'Border','tight');
xlb{i} = xlabel(['(' char(96+i) ')'],'FontSize', 16);
xp = get(xlb{i}, 'position');
xp(2) = xp(2) - yoffset; % update y-position
set(xlb{i}, 'position', xp); % assign new position
end

area() plot covers plot axis

I am creating a graph in MATLAB and then shading the background of the graph to highlight regions. An example of this is as follows:
clc; clear all;
hFig = figure;
y = [0:0.1:2*pi];
x = sin(y);
plot(y,x);
hold on
h(1) = area([0 (2*pi)/2], [1 1],-1);
set(h(1),'FaceColor',[1.0 0.8 0.6],'EdgeColor',[1.0 0.8 0.6]);
h(2) = area([(2*pi)/2 2*pi], [1 1],-1);
set(h(2),'FaceColor',[1.0 0.5 0.5],'EdgeColor',[1.0 0.5 0.5]);
axis tight
set(gca,'children',flipud(get(gca,'children')));
%# centimeters units
X = 14.0; %# paper size
Y = 12.0; %# paper size
xMargin = 1; %# left/right margins from page borders
yMargin = 1; %# bottom/top margins from page borders
xSize = X - 2*xMargin; %# figure size on paper (widht & hieght)
ySize = Y - 2*yMargin; %# figure size on paper (widht & hieght)
set(hFig, 'PaperUnits','centimeters')
set(hFig, 'PaperSize',[X Y])
set(hFig, 'PaperPosition',[xMargin yMargin xSize ySize])
set(hFig, 'PaperOrientation','portrait')
print('example','-dpdf','-r0');
In MATLAB the plot looks like this:
But the generated pdf file looks as follows:
Is there a command to force the axis lines back on top of the shaded areas as it is in the MATLAB plot?
Thanks
When I run the script (R2012b) also the in the "figure" the axis are masked by the two areas (and in the ".pdf" as well).
It seem the problem is related to the plotting rather than the conversion to ".pdf".
In particular the problem seems due to a coupling effect of the defined areas size and "axis tight" setting.
So I've sligthly reduced the areas size, replaced "axis tight" with the explicit defintion of "xlim" and "ylim".
Also, I've increased the axis "linewidth".
clc; clear all;
hFig = figure;
y = [0:0.1:2*pi];
x = sin(y);
plot(y,x);
hold on
% Modified area extend
% h(1) = area([0 (2*pi)/2], [1 1],-1);
h(1) = area([0.02 (2*pi)/2], [.99 .99],-.995);
set(h(1),'FaceColor',[1.0 0.8 0.6],'EdgeColor',[1.0 0.8 0.6]);
% Modified area extend
% h(2) = area([(2*pi)/2 2*pi], [1 1],-1);
h(2) = area([(2*pi)/2 2*pi-.01], [.99 .99],-.995);
set(h(2),'FaceColor',[1.0 0.5 0.5],'EdgeColor',[1.0 0.5 0.5]);
% Replaced "axis tight with explicit "xlim" and "ylim"
% axis tight
set(gca,'xlim',[0 2*pi],'ylim',[-1 1])
% Increased axis "linewidth" (notr strictly necessary
set(gca,'linewidth',1)
set(gca,'children',flipud(get(gca,'children')));
%# centimeters units
X = 14.0; %# paper size
Y = 12.0; %# paper size
xMargin = 1; %# left/right margins from page borders
yMargin = 1; %# bottom/top margins from page borders
xSize = X - 2*xMargin; %# figure size on paper (widht & hieght)
ySize = Y - 2*yMargin; %# figure size on paper (widht & hieght)
set(hFig, 'PaperUnits','centimeters')
set(hFig, 'PaperSize',[X Y])
set(hFig, 'PaperPosition',[xMargin yMargin xSize ySize])
set(hFig, 'PaperOrientation','portrait')
print('example','-dpdf','-r0');
Hope this helps.
The fix was simple, just had to add
set(gca,'layer','top');
to force the axis ontop of the boxes.

MATLAB adding slider on a figure

I have a 576x576x150 matrix. Each 576x576 set represents an image. When I want to plot one frame I do it by using the plot command:
figure(1);
imshow(B(:,:,45),[]) % plots frame 45
title('45') % tells frame number
However I would like to add a slider to the plot, so I can move from 1-150 frame within the figure.I've seen examples of people using uicontrol but I don't know how to code it. In addition to that, I would like to have a title on top of the figure telling me the frame number.
Here is how I do it. I like to keep a single function that does the plotting so you don't recycle commands elsewhere. You could replace the first two lines by function test(B) to use you own B matrix. This code is pretty easy to extend. You will also want to play with the layout to suit your purpose.
function test
B=rand(576,576,150);
fig=figure(100);
set(fig,'Name','Image','Toolbar','figure',...
'NumberTitle','off')
% Create an axes to plot in
axes('Position',[.15 .05 .7 .9]);
% sliders for epsilon and lambda
slider1_handle=uicontrol(fig,'Style','slider','Max',150,'Min',1,...
'Value',2,'SliderStep',[1/(150-1) 10/(150-1)],...
'Units','normalized','Position',[.02 .02 .14 .05]);
uicontrol(fig,'Style','text','Units','normalized','Position',[.02 .07 .14 .04],...
'String','Choose frame');
% Set up callbacks
vars=struct('slider1_handle',slider1_handle,'B',B);
set(slider1_handle,'Callback',{#slider1_callback,vars});
plotterfcn(vars)
% End of main file
% Callback subfunctions to support UI actions
function slider1_callback(~,~,vars)
% Run slider1 which controls value of epsilon
plotterfcn(vars)
function plotterfcn(vars)
% Plots the image
imshow(vars.B(:,:,get(vars.slider1_handle,'Value')));
title(num2str(get(vars.slider1_handle,'Value')));
The idea is to use uicontrol() to enable sliding/scrolling.
The following code is for scrolling (created by Evan Brooks, you can modify it to sliding):
function scrollfigdemo
% create new figure window
f = figure;
set(f,'doublebuffer', 'on', 'resize', 'off')
% set columns of plots
cols = 2;
% create 5 data sets to plot
x=0:1e-2:2*pi;
y{1}=sin(x);
y{2}=cos(x);
y{3}=tan(x);
y{4}=x.^2;
y{5}=x.^3;
% determine required rows of plots
rows = ceil(length(y)/cols);
% increase figure width for additional axes
fpos = get(gcf, 'position');
scrnsz = get(0, 'screensize');
fwidth = min([fpos(3)*cols, scrnsz(3)-20]);
fheight = fwidth/cols*.75; % maintain aspect ratio
set(gcf, 'position', [10 fpos(2) fwidth fheight])
% setup all axes
buf = .15/cols; % buffer between axes & between left edge of figure and axes
awidth = (1-buf*cols-.08/cols)/cols; % width of all axes
aidx = 1;
rowidx = 0;
while aidx <= length(y)
for i = 0:cols-1
if aidx+i <= length(y)
start = buf + buf*i + awidth*i;
apos{aidx+i} = [start 1-rowidx-.92 awidth .85];
a{aidx+i} = axes('position', apos{aidx+i});
end
end
rowidx = rowidx + 1; % increment row
aidx = aidx + cols; % increment index of axes
end
% make plots
axes(a{1}), plot(x,y{1}), title('sine'), xlabel('x'), ylabel('sin(x)')
axes(a{2}), plot(x,y{2}), title('cosine'), xlabel('x'), ylabel('cos(x)')
axes(a{3}), plot(x,y{3}), title('tangent'), xlabel('x'), ylabel('tan(x)')
axes(a{4}), plot(x,y{4}), title('x^2'), xlabel('x'), ylabel('x^2')
axes(a{5}), plot(x,y{5}), title('x^3'), xlabel('x'), ylabel('x^3')
% determine the position of the scrollbar & its limits
swidth = max([.03/cols, 16/scrnsz(3)]);
ypos = [1-swidth 0 swidth 1];
ymax = 0;
ymin = -1*(rows-1);
% build the callback that will be executed on scrolling
clbk = '';
for i = 1:length(a)
line = ['set(',num2str(a{i},'%.13f'),',''position'',[', ...
num2str(apos{i}(1)),' ',num2str(apos{i}(2)),'-get(gcbo,''value'') ', num2str(apos{i}(3)), ...
' ', num2str(apos{i}(4)),'])'];
if i ~= length(a)
line = [line,','];
end
clbk = [clbk,line];
end
% create the slider
uicontrol('style','slider', ...
'units','normalized','position',ypos, ...
'callback',clbk,'min',ymin,'max',ymax,'value',0);

how to draw three graphics on the same figure?

That's how I draw two graphics (thanks for guys who helped me to do that):
clear
logsFolder = 'C:\logs\';
stocks = {'log'};
for stock = stocks
filename = [logsFolder stock{1} '.log'];
fLog = fopen(filename);
data = textscan(fLog, '%f:%f:%f:%f %f %f %f');
fclose(fLog);
% hh:min:sec:millisec
secvec = [60*60 60 1 1e-3];
x = [data{1:4}] * secvec';
y = data{5};
yPrice = data{6};
xindays = x / (24*60*60);
figure;
[AX,H1,H2] = plotyy(xindays,y,xindays,yPrice);
set(AX(1),'xtick',[]);
lo1 = min(y);
hi1 = max(y);
lo2 = min(yPrice);
hi2 = max(yPrice);
if (hi2/lo2 > hi1/lo1)
ylim(AX(1),[lo1 hi2/lo2 * lo1]);
ylim(AX(2),[lo2 hi2]);
else
ylim(AX(1),[lo1 hi1]);
ylim(AX(2),[lo2 hi1/lo1 * lo2]);
end
ticklabelformat(AX(2),'y','%g')
ticklabelformat(AX(2),'x',{#tick2datestr,'x','HH:MM:SS'})
title(stock);
% iNeedToDrawThat = data{7}
end
Input file example is available here As you can see my file contains the last column which I also want to display. The range should be from 0 (at the bottom of figure) to the maximum value (at the up of the graph). So I need to draw three graphics somehow. It's ok to omit axis with labels for the third graph as I already have two axis and I have no place to add third one. However it's ok to "overlap" two axis if possible.
I have no idea how to do that so I'm looking for your help.
I've tried that but it doesn't work:
figure;
[AX,H1,H2] = plotyy(xindays,y,xindays,yPrice);
hold on;
volume = data{7};
plot(xindays, volume);
hold off;
I have already mentioned a similar question in the comments, it should give you plenty of ideas...
Anyway, I've put together a solution to plot multiple y axes. Right now the code is a bit involved, but it should be possible to refactor a re-usable function out of it (like the addaxis function on the File Exchange).
The idea is to first plot each curve in a separate axis (all superimposed), and make them transparent (except the bottom one). Next we create copies of this set of axes and shift them along the x-direction. We also make those copies transparent, but now we can show the tick-marks along the y-axis of each. Finally we give them correct z-order, and link the x and y limits so that we can use the pan and zoom functionality.
%# read and parse data from file
fid = fopen('log.log','rt');
C = textscan(fid, '%s %f %f %f', 'CollectOutput',true);
fclose(fid);
dt = datenum(C{1}, 'HH:MM:SS:FFF');
data = C{2};
NUM = size(data,2);
%# create a wider figure
hFig = figure('Position',get(0,'DefaultFigurePosition').*[1 1 1.7 1]);
%# some properties
clr = lines(NUM);
bgClr = get(0,'DefaultFigureColor');
pos = get(0,'DefaultAxesPosition');
pp = 0.1; % shift in normalized units: pos(1)
%# create plot axes (make axis invisible)
hAx = zeros(NUM,1);
for i=1:NUM
hAx(i) = axes('Parent',hFig, 'Color','none', ...
'XColor',bgClr, 'YColor',bgClr, ...
'Units','normalized', 'Position',pos+[(NUM-1)*pp 0 -(NUM-1)*pp 0]);
line(dt, data(:,i), 'Color',clr(i,:), 'Parent',hAx(i))
end
axis(hAx, 'tight') %# tight x/y limits
%# create shifted copies of axes to show y-ticks
hAxx = zeros(size(hAx));
for i=1:NUM
hAxx(i) = copyobj(hAx(i), hFig);
delete(get(hAxx(i),'Children')); %# keep only axis
set(hAxx(i), 'YColor',clr(i,:), ...
'Units','normalized', 'Position',pos+[(NUM-i)*pp 0 -(NUM-i)*pp 0]);
ylabel(hAxx(i), sprintf('Axis %d',i))
end
xlabel(hAxx(1), 'datetime')
title(hAxx(1), 'Log')
datetick(hAxx(1), 'x', 'HH:MM', 'keeplimits')
%# set 1st axis copy as current axis
set(hFig, 'CurrentAxes',hAxx(1))
%# adjust ticks of axes
set(hAx(1), 'Color','w') %# give white bg to 1st axis
set(hAxx(1), 'XColor','k') %# show xticks of 1st axis copy
set(hAxx(2:end), 'XTick',[], 'XTickLabel',[])
set(hAx, 'XTick',[], 'XTickLabel',[], 'YTick',[], 'YTickLabel',[])
%# fix z-order
for i=3:-1:1, uistack(hAxx(i),'top'), end
uistack(hAx(1), 'bottom')
%# link x/y limits so that panning/zooming works
lh = cell(NUM+1,1);
for i=1:NUM
lh{i} = linkprop([hAxx(i);hAx(i)], 'YLim');
end
lh{end} = linkprop([hAxx;hAx], 'XLim');
The result:
The panning/zooming is a bit funny, you have to initiate them by starting to drag from the side (the shifted colored axes). This is because the first one (corresponding to the blue line) is the one on top, thus catches all mouse clicks.
Note: I see you are using a custom function ticklabelformat, which I haven't tested in combination with the above code. I will leave that part to you..
HTH
sample use of hold on
figure;
plot(x1,y1);
hold on
plot(x2,y2);
plot(x3,y3);
hold off
do "figure" and "hold on" only once outside the loop. then plot all the graphs you need
figure;
[AX,H1,H2] = plotyy(xindays,y,xindays,yPrice);
hold on;
volume = data{7};
plot(xindays, volume);
hold off;
if you do it the way you suggested using hold on, i.e. use plotyy() first then the axes won't adjust so if you 3rd series is out of the range of your first set of axes then it won't appear. Try just flipping them and see if that produces a result?
volume = data{7};
plot(xindays, volume);
hold on;
[AX,H1,H2] = plotyy(xindays,y,xindays,yPrice);
This way the axes should adjust
For example:
t = 1:10;
x = t*2;
y = t*-2;
z = x + 1000;
Now compare
plot(t,z, 'r')
hold on
plotyy(t,x, t,y)
to
plotyy(t,x, t,y)
hold on
plot(t,z, 'r')