How to plot 3D vectors on a 2D plot?

Hi everyone! I need to create a 2D plot where the elements that are at z = 1 must be at the same level of the elements at x and y but these elements along z must be highlighted against the background on x and y in order to be distinguished. How can I do it?

[Star Strider]

Where are the data?

Uz = unzip('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1009395/Prova_test.zip');
Uz2 = [num2cell((1:numel(Uz))') Uz']

Uz2 = 120×2 cell array
    {[ 1]}    {'Prova_test/codice_opcode.asv'                       }
    {[ 2]}    {'Prova_test/codice_opcode.m'                         }
    {[ 3]}    {'Prova_test/Scenari/'                                }
    {[ 4]}    {'Prova_test/Scenari/Nuovascena.stl'                  }
    {[ 5]}    {'Prova_test/Subfunctions/'                           }
    {[ 6]}    {'Prova_test/Subfunctions/matlab/'                    }
    {[ 7]}    {'Prova_test/Subfunctions/matlab/deer.ply'            }
    {[ 8]}    {'Prova_test/Subfunctions/matlab/opcodemesh.m'        }
    {[ 9]}    {'Prova_test/Subfunctions/matlab/opcodemeshdemo.m'    }
    {[10]}    {'Prova_test/Subfunctions/matlab/opcodemeshmex.mexw64'}
    {[11]}    {'Prova_test/Subfunctions/matlab/read_ply2.m'         }
    {[12]}    {'Prova_test/Subfunctions/opcode/'                    }
    {[13]}    {'Prova_test/Subfunctions/opcode/CMakeLists.txt'      }
    {[14]}    {'Prova_test/Subfunctions/opcode/Ice/'                }
    {[15]}    {'Prova_test/Subfunctions/opcode/Ice/IceAABB.cpp'     }
    {[16]}    {'Prova_test/Subfunctions/opcode/Ice/IceAABB.h'       }

.

Answer 1

[Cris LaPierre]

The solution likely varies depending on your data, but I would probably first look into using imagesc:

imagesc(x,y,C)

This way, the difference in Z is captured in the color displayed in the figure.

imagesc(new_x,new_y,hit);

[Loren99]

@Cris LaPierre I've just tried as you can see from the following figure but it is not okay because I want the shapes at z=1 to be reproduced on the x, y plane. Maybe is there a command that in scatter3 allows me to highlight the elements at z=1 with a different color with respect to x and y elements at z=0? Then I can apply view (0,90) to see the resulting map from the top

[Cris LaPierre]

It's hard to give anything specific without having your data. Consider saving your variables to a mat file and attaching that file to your post using the paperclip icon.

[Loren99]

@Cris LaPierre I cannot save the variables to a mat file because of their huge dimension. However I have attached a zip file with the main called 'codice_opcode'

[Cris LaPierre]

Ok, I see. I'll have to look more into imagesc, but the simplest approach for now might be to use gscatter, assuming hit is just 0 or 1

gscatter(new_x,new_y,hit);

Edit: Looked more

For an image, your data should be an array, not a vector. Use reshape to convert hit into a 12001x14001 array, and then use imagesc to view it. This is quicker than using scatter, both in creating and saving.

Ihit = reshape(hit,size(Z));
imagesc(Ihit);
axis xy

[Loren99]

@Cris LaPierre thank you very much for both the methods! Just a curiosity. In gscatter, is there a way to not plot the legend as well? because I need the clean image

[Cris LaPierre]

Yes. Use this syntax, where doleg is either 'on' or 'off'.

gscatter(x,y,g,clr,sym,siz,doleg)

You can't skip an input, so your code might look like this (empty brackets uses the default value)

gscatter(new_x,new_y,hit,[],[],[],'off');

You can explore these and other optional inputs in the linked documentation page.