Enlarging models in MATLAB - matlab

Question

Im trying to create a project in MATLAB where i project a heat map matrix on to a cylinder in MATLAB but i'm bumping in to all kinds of issues.
Im using MATLAB version R2019b(Latest version).
Now my first issue id like to adress is is the modells being absolutely tiny even when i zoom in to the max.
Is there any way to make these models larger or to display them in a separate window ??
Also my second question is the regarding the scaling. As you can see the scale on the Z-axis of the cylinder goes to 512. any way to get a larger more detailed image where i can see each point on that scale?
clear vars
filename =
['/Users/gomer/Documents/Datavisualisering/Projekt/data/day/filenames.txt'];
%This line simply gives us a table of all filenames in this file.
T = readtable(filename);
tsize = size(T);
%extracts the content of the table as a categorical array.
%%
%
% {rownumber,variablenumber}. {100,1} = row 100, variable 1.
%converts the categorical array into a string array.
%joins the string array across the column.
%string(T{100:105,1}); implies from row 100 to row 105 and use variable 1.
%This line simply adds the name of the file at row 100 to the path of the
%file. Hnece we get a full filepath.
filename = strcat('/Users/gomer/Documents/Datavisualisering/Projekt/data/day/', string(T{100,1}));
map100 = getHeatMap(filename);
%%
%
filename = strcat('/Users/gomer/Documents/Datavisualisering/Projekt/data/day/', string(T{1000,1}));
map1000 = getHeatMap(filename);
%creates a image
k=imshow(map100);
%creates a colormap.
%gca returns the current axes (or standalone visualization) in the current figure.
%hence the command just works top down and affects last image displayed.
colormap(gca, 'jet');
k=imshow(map1000);
colormap(gca, "jet");
function heat = getHeatMap(filename)
%Returns a struct with info about the file.
s = dir(filename);
%Opens a file for reading, hence the 'r'.
fin=fopen(filename,'r');
%A = fread(fileID,sizeA,precision)
%reads file data into an array, A, with dimensions, sizeA, and positions the file pointer after the last value read.
%fread populates A in column order.
I=fread(fin,s.bytes,'uint8=>uint8');
%The uint16 function converts a Input array, specified as a scalar, vector, matrix, or multidimensional array.
%Converts the values in to type uint16 and creates a Matrix with the values.
%Looks more like we are just calculating the size of values to be
%deducted from matrix size (no idea why).
w = uint16(I(1))+256*uint16(I(2));
h = uint16(I(3))+256*uint16(I(4));
skip = s.bytes - w*h + 1;
IN = I(skip:1:s.bytes);
%reshape(A,sz) reshapes A using the size vector, sz, to define size(B). For example, reshape(A,[2,3]) reshapes A into a 2-by-3 matrix.
%sz must contain at least 2 elements, and prod(sz) must be the same as numel(A).
%single(X) converts the values in X to single precision.
Z=single(reshape(IN,w,h));
%Interpolate the values.
%telling the system which points to interpolate in between.
Z=griddedInterpolant(Z');
y_range = linspace(1.0,single(h),360);
x_range = linspace(1.0,single(w),512);
%Used to apecify the query points (points in between which we want
%interpolation) as vectors (this is to get a more continues image).
%specifies the query points as grid vectors.
%Use this syntax to conserve memory when you want to query a large grid of points.
heat = uint8(Z({y_range, x_range}));
end
Thank you

Answer 1

Resizing Figure Window
Copying your script to a .m and running it instead of a live .mlx file will automatically create all the figures in a separate window by default. To adjust the size of the figures the following the position property can be modified. To adjust the scale functions xticks(), yticks() and zticks() can be used. These three scale functions take in an array representing all the line markers along the respective axis/scale.
Test Plot Script:
X_Position = 10;
Y_Position = 10;
Width = 1000;
Height = 500;
%Configuring the figure settings%
figure('Position', [X_Position Y_Position Width Height])
%Test plot (replace with your plot)%
Data = [1 2 3 4 5 6];
plot(Data);
Plotting Heatmaps on a Cylindrical Surfaces
Method 1: Using warp() Function
Haven't delved into which orientation the data should be set as but this is an option to use the warp() function to wrap the heatmap around a cylinder. They're most likely other 3D plotting options if specific points are of interest. The points of the cylinder to be plotted are generated using the cylinder() function which returns the xyz-coordinates of the cylinder's wireframe. The fourth input argument into the warp() function serves and a colormap in this case it is proportional to the heatmap values.
load('HeatMapMatrix.mat');
%Setting up the figure%
clf;
close all;
figure('Position', [10 10 1000 500])
%Creating the cylinder%
Cylinder_Radius = 360;
Cylinder_Height = 512;
[X,Y,Z] = cylinder(Cylinder_Radius,Cylinder_Height-1);
%Warping the heatmap along the cylinder%
subplot(1,2,1); warp(X,Y,Cylinder_Height.*Z,map100');
colormap(gca,'jet');
subplot(1,2,2); warp(X,Y,Cylinder_Height.*Z,map100);
colormap(gca,'jet');
Method 2: Plotting All Points and Using surf() Function:
In this case, the coordinates for a cylinder are generated by first finding the coordinates of the circumference of the cylinder. This is done by using the sin() and cos() relationships:
X-Points = Radius × cos(𝜃)
Y-Points = Radius × sin(𝜃)
This results in the xy-coordinates of the cylinder's circle. These xy-coordinates need to be duplicated using repmat() to be later used for the varying heights. The process can be described best with a diagram as follows:
Four matrices above are created to plot each Heat Data point corresponding to an xyz-coordinate. The x and y coordinates are repeated in every row of matrices X-Points and Y_Points since those are constant for the repeating circles. The columns of the matrix Z-Points are also duplicates of each other since the heights should be constant for each row corresponding to each circle.
load('HeatMapMatrix.mat');
Radius = 20;
Number_Of_Data_Points = 360;
Theta = linspace(0,2*pi,Number_Of_Data_Points);
%The xy values according to radius and number of points%
X_Points = Radius*cos(Theta);
Y_Points = Radius*sin(Theta);
map100 = rot90(map100);
Sample_Range = 255 - 0;
Temperature_Range = 450 - 50;
Multiplier = Temperature_Range/Sample_Range;
map100 = map100.*Multiplier + 50;
Height = 512;
X_Points = repmat(X_Points,Height,1);
Y_Points = repmat(Y_Points,Height,1);
Z_Points = (1:512)';
Z_Points = repmat(Z_Points,1,Number_Of_Data_Points);
clf;
close;
figure('Position', [10 10 800 500])
Offset = 200;
subplot(1,3,1:2); Surface = surf(Y_Points,X_Points,Z_Points,'Cdata',map100);
title("3D Heatmap Plot");
zlabel("Height");
shading interp
colorbar
% direction = [0 1 0];
% rotate(Surface,direction,90)
Maximum_Value = 450;
Minimum_Value = 50;
caxis([Minimum_Value Maximum_Value]);
subplot(1,3,3); imshow(rot90(rot90(map100)));
colormap(gca, 'default');
title("Flat Heatmap Plot");
caxis([Minimum_Value Maximum_Value]);
colorbar;
Ran using MATLAB R2019b