change color scheme of a scatter plot

here above you can see i have a 2-D Scatter plot. now i want to change the color scheme.

for all the values

1. values <= 10 ----- green color
2. (10<values<=20) ----- yellow color (for intermediate values i.e for 13 or 16 let yellow shades become darker and similar for all 4 ranges)
3. (20 < values <= 50) ----- orange color
4. (50 < values ) ---- red color.

Answer 1

[Image Analyst]

Try this:

% values <= 10     -----  green color
% (10<values<=20)  ----- yellow color           (for intermediate values i.e for 13 or 16 let yellow shades become darker and similar for all 4 ranges)
% (20 < values <= 50) ----- orange color
% (50 <  values ) ---- red color.
% First we need to create sample data because the original poster did not include it.
X = 8 : 2 : 16;
Y = 8 : 2 : 14;
[x, y] = meshgrid(X, Y);
x = x(:); % Make into 1-D vector.
y = y(:); % Make into 1-D vector.
z = randi(70, length(x), 1);
% Now we have our data and we can begin.  
% We need to make up a colormap for the markers based on the value of z.
markerColors = zeros(length(x), 3);
rows = z <= 10;
markerColors(rows, :) = repmat([0, 1, 0], sum(rows), 1); % Green
rows = z > 10 & z <= 20;
markerColors(rows, :) = repmat([1, 1, 0], sum(rows), 1); % Yellow
rows = z > 20 & z <= 50;
markerColors(rows, :) = repmat([1, 0.59, 0], sum(rows), 1); % Orange
rows = z > 50;
markerColors(rows, :) = repmat([1, 0, 0], sum(rows), 1); % Red
scatter(x, y, 300, markerColors, 'filled');
grid on;

Answer 2

[KSSV]

You should follow like this demo:

n = 100 ;
x = 1:n ;
y = rand(size(x)) ;
% divide based on values 
idx1 = y >=0 & y<0.25 ;
idx2 = y >=0.25 & y<0.5 ;
idx3 = y >=0.5 & y<0.75 ;
idx4 = y >=0.75 & y < 1 ;

figure
hold on
plot(x(idx1),y(idx1),'*r') 
plot(x(idx2),y(idx2),'*b') 
plot(x(idx3),y(idx3),'*g') 
plot(x(idx4),y(idx4),'*k') 

[Sajid Afaque]

but here i have 3 values to plot and i am using to plot.

i need my Z values which are above in the circular form to have color scheme according to my condition

scatter(x,y,[],z) 

[KSSV]

Okay..you can use scatter instead of plot....

[Sajid Afaque]

as i am new to this concept,can you please explain me the above code.

[darova]

What kind of explanation do you need?

[Sajid Afaque]

i figured it out , thank you

Answer 3

[Pamudu Ranasinghe]

use gscatter it is easy

https://in.mathworks.com/help/stats/gscatter.html