How to overlay two surf plots?

Hi everyone,

I am trying to overlay the contour stroke shape into the colorful surf plot

Here the code i've tried but it doesnt work, it only show the left image above

hold on
surf(X,Y,-M1); surf(-X,Y,M1);   %Reflection along y axis
surf(X,Y,Ta);  surf(-X,Y,Ta);      %Stroke Contour

[Walter Roberson]

surf(X,Y,-M1); surf(-X,Y,M1);   %Reflection along y axis

I have to wonder whether that should be

surf(X,Y,-M1); surf(-X,fliplr(Y),M1);   %Reflection along y axis

or

surf(X,Y,-M1); surf(-X,flipud(Y),M1);   %Reflection along y axis

or something like that?

[LEONG SING YEW]

Hi, i test two of your codes and i found that

surf(X,Y,-M1); surf(-X,Y,M1);   %Reflection along y axis

is the same as the

surf(X,Y,-M1); surf(-X,flipud(Y),M1);   %Reflection along y axis

hold on
surf(-X,flipud(Y),M1); %surf(X,Y,-M1);  %Left image - contour
%surf(-X,Y,Ta);  
surf(X,Y,Ta); %right image - stroke contour

Do you have any idea on how to overlay the right image to the left image?

[Walter Roberson]

It would help if we had your data to work with -- X, Y, and M1 and Ta

[LEONG SING YEW]

Yes you may have my code and my data in the csv attachment,

The picture shown is what i'm trying to do: to overlay the black stroke of the flame front on the colorful surf plot

colormap jet

%{
    Read data
                %}

filename0   = '0.csv';
Data0       = csvread(filename0,6,0);

filename1   = '360.csv';
Data1       = csvread(filename1,6,0);%skip 6 header lines

%{
    Data Extraction
                        %}

X_Data   = Data0(:,2);          Y_Data    = Data0(:,1);  %x and y coordinates


%Extract both temperature and x-velocity data
T_Data0  =   Data0(:,8);        V_Data0   = Data0(:,9);

T_Data1  =   Data1(:,8);        V_Data1   = Data1(:,9);

V_Data1 = V_Data1-V_Data0;  %Fluctuation velocity, v'
V_Data1(T_Data1>400)=0; %Temperature outside the flame front is not considered


T_1=V_Data1-1;  %Create flame front stroke by darken it using caxis later, or any alternative method
T_1(T_Data1>500)=NaN; T_1(T_Data1<325)=NaN; %Only circumference of flame front is needed

%{
    Surf
           %}
[x,~,xi]=unique(X_Data*1e3/2); %convert m to mm
[y,~,yi]=unique(Y_Data*1e3/2); 
subs=[xi yi];%use the indices instead of values as coordinates
[X,Y]=ndgrid(x,y);%generate the grid surf() expects

Ta =accumarray(subs,T_1,[],[],NaN);
M1=accumarray(subs,V_Data1,[],[],NaN);%fill missing with NaN

hold on
surf(-X,Y,M1); surf(X,Y,-M1); %Reflection along y-axis
surf(-X,Y,Ta);  surf(X,Y,Ta); %Stroke Contour

shading interp; c=colorbar;
xlim([-2 2]); ylim([-0.5 3.4]);
xlabel("x/R (mm)"+newline);ylabel("y/R (mm)"+newline)
title(c,"v'/U_o",'FontSize',9,'FontWeight','bold');
title('Phase = 0\circ')
caxis([-.1 .1])  %Set the range
view(0,90);

Answer 1

[Walter Roberson]

view(0,-90)

[LEONG SING YEW]

Thank you!

[LEONG SING YEW]

Hi,

I use xy plots instead of using the the surf plot for the contour line for better view.

The images attached below can be seen that the surf image is blocking the stroke shape on each side, i wonder if the xy plot stroke shape can be shift towards/backward so it can overlay the surf plot. Appreciate your help again.

Here's the code:

T_Data1(T_Data1>390) = 300;
[A B]=size(T_Data1);
X_new = zeros(A,1); Y_new = zeros(A,1);
for i = 1:A;
    if T_Data1(i,:)>350; 
        X_new(i) = X_Data(i);  %retain the value
        Y_new(i) = Y_Data(i);
    else 
        continue
    end
end
XY = [X_new*1e3 Y_new*1e3]; 
rows = find(XY(:,2)==0);  
XY(rows,:)=[];  %eliminate rows with value zeros

[~,idx] = unique(XY(:,2)); %which rows have a unique first value
XY = XY(idx,:);            %retain them

[~,idy] = unique(XY(:,1));
XY = XY(idy,:);

X = XY(:,1)/2;
Y = XY(:,2)/2;

plot(-X,Y,'black','linewidth',2); plot(X,Y,'black','linewidth',2)

[Walter Roberson]

plot() creates a 3D plot with empty Z components, and that in turn is treated the same as if the Z components were all 0. You can use plot3() to provide explicit Z coordinates; you would want to use a Z larger than the largest Z in the surf plot.

I wonder if pcolor() would be better than surf() for your purpose? pcolor is a surface plot underneath, but it creates a surface in which all the Z are 0 and the color data is set according to the Z data that was passed to pcolor(). Using Z all 0 can make it easier to draw things on top of it.

[LEONG SING YEW]

omg, i didn't know this command "pcolor" exist, amazing!!! Thank you so much!!!