How to make smoothen 3D surf plot?

Hello,

I'm having a surf plot with spikes. I was wondering how i can do to smooth it.

When I search for methods about this problems,

"interp2" function might be a solution. but, I'm having problems with the dimension and did not manage to do so.

1. I have a matrix (data.GX1) of dimension 60X162 for X values in surf function.
2. I have a matrix (data.GY1) of dimension 60X162 for Y values in surf fucntion.
3. I have a matrix (data.Y1) of dimension 60X162 for Z values in surf fucntion.

If possible, I would appreciate it if you could write a code using interp2.

Otherwise, I'd be very glad for some hints on how to do this.

%% Code : Question about "How to smooth surf spikes"
clear ; close all; clc
load('data.mat') 
% GX1 = data.GX1; "X values" in struture.
% GY1 = data.GY1; "Y values" in struture.
% Y1 = data.Y1; "Z values" in struture.
%% Define Colormap 
fig.colormap = load('Question.mat').Question; % Colormap Name : Question 
%% Figure
tp.ax{1,1} = figure(1);
set(tp.ax{1,1},'OuterPosition',[170,140,1600,1000]);
% Plotting : Surf
tp.h1 = surf(data.GX1,data.GY1,(-1)*data.Y1); hold on;
set(tp.h1,'FaceAlpha',1,'Edgecolor','interp','LineStyle','none','Marker','none');
shading interp; 
colormap(fig.colormap);
tp.Cb = colorbar;
caxis([-10 16]);
set(tp.Cb,'Ticks',-10:2:16);
tp.Cb.Label.FontSize = 30;
tp.Cb.Label.String = {'Depth variation (cm)'};
axis equal
xlabel('Distance from the center zone (cm)','Fontsize',12);
ylabel('Distance from the center zone (cm)','Fontsize',12);

Answer 1

[Mathieu NOE]

hello

I can make you these two suggestions , one is based on smoothn (see Fex : smoothn - File Exchange - MATLAB Central (mathworks.com), also in attachment) ), the other is using smooth2a (also in attachment)

hope it helps

Result with smoothn

Result with smooth2a

Code

%% Code : Question about "How to smooth surf spikes"
clear ; close all; clc
load('data.mat') 
% GX1 = data.GX1; "X values" in struture.
% GY1 = data.GY1; "Y values" in struture.
% Y1 = data.Y1; "Z values" in struture.

X = data.GX1;
Y = data.GY1;
Z = (-1)*data.Y1;
clear data

%% Define Colormap 
fig.colormap = load('Question.mat').Question; % Colormap Name : Question 
%% Figure
tp.ax{1,1} = figure(1);
set(tp.ax{1,1},'OuterPosition',[170,140,1600,1000]);
% Plotting : Surf
tp.h1 = surf(X,Y,Z); 
set(tp.h1,'FaceAlpha',1,'Edgecolor','interp','LineStyle','none','Marker','none');
shading interp; 
colormap(fig.colormap);
tp.Cb = colorbar;
caxis([-10 16]);
set(tp.Cb,'Ticks',-10:2:16);
tp.Cb.Label.FontSize = 30;
tp.Cb.Label.String = {'Depth variation (cm)'};
axis equal
xlabel('Distance from the center zone (cm)','Fontsize',12);
ylabel('Distance from the center zone (cm)','Fontsize',12);

  
%% Figure 2 (smoothn)
s_factor = 1; % smoothing parameter
Zs = smoothn(Z,s_factor,'robust'); % FEX : https://fr.mathworks.com/matlabcentral/fileexchange/25634-smoothn/

  tp.ax{1,1} = figure(2);
set(tp.ax{1,1},'OuterPosition',[170,140,1600,1000]);
% Plotting : Surf
tp.h1 = surf(X,Y,Zs); 
set(tp.h1,'FaceAlpha',1,'Edgecolor','interp','LineStyle','none','Marker','none');
shading interp; 
colormap(fig.colormap);
tp.Cb = colorbar;
caxis([-10 16]);
set(tp.Cb,'Ticks',-10:2:16);
tp.Cb.Label.FontSize = 30;
tp.Cb.Label.String = {'Depth variation (cm)'};
axis equal
xlabel('Distance from the center zone (cm)','Fontsize',12);
ylabel('Distance from the center zone (cm)','Fontsize',12);

  
  %% Figure 3 (smooth2a)
ZZ = smooth2a(Z,3,3);

tp.ax{1,1} = figure(3);
set(tp.ax{1,1},'OuterPosition',[170,140,1600,1000]);
% Plotting : Surf
tp.h1 = surf(X,Y,ZZ); 
set(tp.h1,'FaceAlpha',1,'Edgecolor','interp','LineStyle','none','Marker','none');
shading interp; 
colormap(fig.colormap);
tp.Cb = colorbar;
caxis([-10 16]);
set(tp.Cb,'Ticks',-10:2:16);
tp.Cb.Label.FontSize = 30;
tp.Cb.Label.String = {'Depth variation (cm)'};
axis equal
xlabel('Distance from the center zone (cm)','Fontsize',12);
ylabel('Distance from the center zone (cm)','Fontsize',12);

[병진]

Thank you,

I think this method is the perfect answer for me.

Again, thank you for your reply.

[Sam Chak]

@병진, Don't forget to accept the helpful perfect answer.