find elemets of matrix based on logical conditions

Dear MATLAB experts,

I have a matrix and wanted to find elements that meet the condition written as goodpts. I tried find function returns a one column array. I could show want I wanted using scatter3.

Thank you in advance.

points=readtable('points.txt');
points=table2array(points);


x_p=points(:,1);
y_p=points(:,2);
z_p=points(:,3);
t_p=points(:,4);

goodpts= z_p>-5 & z_p<5 & x_p>-20 & x_p<20 & -20<y_p & y_p<20 ;

good_points=find(points(goodpts));

scatter3(x_p(goodpts),y_p(goodpts),z_p(goodpts),2,t_p(goodpts),'filled')   

[KSSV]

What is your question. It seems you got what you want.

[Hamid]

@KSSV Thank you for reply.

I wanted a matrix contains all of these points but good_points includes only one column and not x,y,z of my data.

In other words, record what has been shown in the scatter3 graph.

[Stephen23]

"In other words, record what has been shown in the scatter3 graph."

x_shown_in_graph = x_p(goodpts);
y_shown_in_graph = y_p(goodpts);
z_shown_in_graph = z_p(goodpts);

[Hamid]

@Stephen23 Thank you so much.

Answer 1

[KSSV]

points=readtable('points.txt');
points=table2array(points);

x_p=points(:,1);
y_p=points(:,2);
z_p=points(:,3);
t_p=points(:,4);

goodpts= z_p>-5 & z_p<5 & x_p>-20 & x_p<20 & -20<y_p & y_p<20 ;
good_points=find(points(goodpts));
x_p_goodpts = x_p(goodpts) ; 
y_p_goodpts = y_p(goodpts) ;
z_p_goodpts = z_p(goodpts) ;
t_p_goodpts = t_p(goodpts) ; 
scatter3(x_p_goodpts,y_p_goodpts,z_p_goodpts,2,t_p_goodpts,'filled')   

[Hamid]

@KSSV Thanks a lot!