how to make a 3d plot with x,y,z, coordinates and data (t)

Hi, I have x,y,z,t data in a excel file. The x,y,z are coordinates while t is data. How can i plot a 3d plot. the x,y,z are usually in a plane so z is constant. x and y are equispaced and sometimes may not be. how to plot. expecting earliest attention thanks rama

[Walter Roberson]

How do you want to represent your "t" ? As dot size? As color? Ignore the z and treat "t" as if it were z ?

[rama krishna]

i want to represent t as colour as a surface or a mesh. I can ignore z but i want it to be there. is there any function that can handle it without using meshgrid.

[Walter Roberson]

To get a surface or mesh you need to know something about the connectivity of the points.

Consider for example a simple list of 5 points around a circle: connect them in clockwise order and you get a pentagon shape, but connect each to the second closest instead and you get a "star" (pentagram). Likewise if you do not know which of your points connect to which, you cannot know how to build your surface.

[Walter Roberson]

How do you know which points are adjacent?

[rama krishna]

if u know a bit of programming u can tell. btw who r u who waste time of others

Answer 1

[Youssef Khmou]

hi,

try

 plot3(x,y,t);
 scatter3(x,y,t,'r');
 % z is constant !

Answer 2

[Youssef Khmou]

hi ,

as you want to visualize t ( t as function of x and y t=F(x,y)) then i suggest this trick , i show it based on an example ok? :

1)EXAMPLE 1 :

   x=0:0.1:10;
   y=0:0.1:10;
   t=randn(size(x));
   % I ADJUST the lengths so as to map the vectors x and y into matrices 
   X=reshape(x(1:100),10,10);
   Y=reshape(y(1:100),10,10);
   T=reshape(t(1:100),10,10);
   % FIGURE

   surf(X,Y,T);shading interp

2)EXAMPLE2 :

   x=randn(10); % Gaussian Process N(0,1)
   y=randn(10); % same ~N(0,1)
   t=rand(10); %  Random Uniform distribution
   surf(x,y,t);shading interp

i hope this helps , try to apply on your data and see......