In a 3d graph. Can we put limits on z axis w.r.t. x and y axis?

if true
  % code
function [Kraftstoffverbrauch, Drehzahl, Drehmoment]=Kasus2_1(Drehzahl, Drehmoment)
% Modify the dimensions 
nx = length(Drehzahl) ; 
ny = length(Drehmoment) ; 
if nx > ny 
Drehmoment1 = linspace(min(Drehmoment),max(Drehmoment),nx ) ; 
elseif nx<ny
  Drehzahl1 = linspace(min(Drehzahl),max(Drehzahl),ny) ;
end
[num,txt,raw] = xlsread('Mappe2.xlsx') ;
Dz = num(:,1) ; Dz(isnan(Dz))= [ ];
Dm = num(:,2) ;Dm(isnan(Dm))= [ ];
Kv = num(:,3) ;Kv(isnan(Kv))= [ ];
F = scatteredInterpolant([Dz Dm],Kv);
for i= 1:1:nx
for j= 1:1:ny
Kraftstoffverbrauch (i,j) = F(Drehzahl(i),Drehmoment(j));
end
end
surf(Drehzahl,Drehmoment,Kraftstoffverbrauch'),xlabel ('Drehzahl(1/min)');ylabel ('Drehmoment(N.m)'); zlabel ('Kraftstoffverbrauch(kWh/100km)');
title ('Drehmoment vs Drehzahl Diagram');
end

The display of he expected limits can be sssn in the picture

[jonas]

I don't understand what you mean. The "expected" plot is entirely different from the "actual" plot, but your question is about z axis limits? Care to elaborate?

[Shubham Mohan Tatpalliwar]

i have sketched the limits in actual plot ansd you can see the actual values in expected plot

[Shubham Mohan Tatpalliwar]

x=[1000:250:5500] y=[160,180,200,220,220,218,216,215,219,220,220,220,220,220,220,210,200,195,175]

these are the limits of the axis

[jonas]

It is still unclear what you mean. What did you sketch? The thick black line? Do you want to have a non-rectangular grid? If so, then you can just place NaN's where you do not want data. Please upload some data and perhaps a more detailed explanation if you need more help.

[Shubham Mohan Tatpalliwar]

hello jonas Actually the black line you see are the limits of y axis w.r.to x and z axis and the values are in previous comment i was also thinking of NaN but the input could be canged every time

so i just want to have a matrix which would nullify the the data above these limits

like a matrix of idx which has the value 1 within limits and 0 beyond limits.

i would multiply this expected matrix with my result and ultimately would the the graph everytime within limits

Answer 1

[jonas]

I made your code a bit faster and fixed your problem.

%%Load data
[num,txt,raw] = xlsread('Mappe2.xlsx') ;
x = num(:,1);
y = num(:,2);
z = num(:,3);
x(isnan(x)) = [];
y(isnan(y)) = [];
z(isnan(z)) = [];

%%Interpolate
F = scatteredInterpolant([x y],z);
[X,Y] = meshgrid(1000:5500,0:250);
Z = F(X,Y);

%%Define region where you want to keep data
xp = 1000:250:5500; 
yp  =[160,180,200,220,220,218,216,215,219,220,220,220,220,220,220,210,200,195,175];
ax = gca;
xp = [xp max(xp) min(xp) min(xp)];
yp = [yp min(Y(:)) min(Y(:))  yp(1)];

%%Find points inside of this region and remove others
in = inpolygon(X(:),Y(:),xp,yp);
Z(~in) = NaN;

%%Plot
figure;hold on
surf(X,Y,Z,'edgecolor','none')

[Shubham Mohan Tatpalliwar]

i have tried to change the intervals of input to get a particular value of z in the surface plot w.r.t. x and y. but it is working very slow.

could you suggest me anything to make this plotting a bit simpler sothat i could get the desired data faster

[jonas]

Reduce the resolution of the grid in this line:

[X,Y] = meshgrid(1000:5:5500,0:5:250);
                      ↑        ↑

I've changed the step-size from 1 to 5. You could also try griddata or interp2 for interpolation instead of griddedInterpolant.

[Shubham Mohan Tatpalliwar]

Hello, Yesterday i was working on it

and i got at first this type of result but i ignored

AND NOW I AM GETTING THE SAME RESULTS FOR THE SAME PROGRAM

Can u tell me whats wrong with it

[jonas]

Something wrong with the polygon, the lower right corner has not been defined correctly. Make sure to clear variables between runs. Also, it was probably not so wise of me to use axes limits in the definition of the polygon edges. I will update with a more robust approach in a bit.