How to plot a graphic with different markers in a scatter plot?

Hi;

I want to plot a graphic with different shaped markers?

I send a graphic in the attached file. As you see there are 9 dots with grouped as A, B and C. I want to plot each of them with a different marker.

For example;

Dot 1: circle

Dot 2: square

Dot 3: diamond

Dot 4: cross

etc...

This is my Matlab code:

clear;
load -ascii test1.txt;
a=test1(:,1);
b=test1(:,2);
c=test1(:,3);
d=test1(:,4);
e=test1(:,5);
f=test1(:,6);
scatter(a,b, 'r', 'Linewidth',15);
hold on;
scatter(c,d, 'b', 'Linewidth',15);
hold on;
scatter(e,f, 'g', 'Linewidth',15);
xlim ([0.8 1.3]);
ylim([100 180]);
set(gca,'Fontsize',24,'Linewidth',2);
grid;

How can I plot each dot with a different marker shape? An also how can I show these 9 dots in legend?

Thanks a lot..

[dpb]

You mean each group, not each dot, surely???

Make it even simpler to respond, attach the .mat file or just past the data points in as code block.

Is there a corollary grouping variable available? If not, how to know to group in the specific manner?

[SEVAL DONERTAS]

I want to plot each "9 dots" in the graphic with "different marker.". Not each group.

May be I need to make a change in the code, but how can I do that?

I add the matlab code in the attcahed file..

[Adam]

You would need to create 9 different scatter plots and plot them all together on the same axes.

[SEVAL DONERTAS]

I attch my ."txt file" and my matlab code in the attached file.

How can I create 9 different scatter plots together in same axes?

Regards,

Answer 1

[meghannmarie]

Is this what you mean? This is assuming that a,b,c,d,e,f are 3 element vectors.

clear;

load -ascii test1.txt;

a=test1(:,1);
b=test1(:,2);
c=test1(:,3);
d=test1(:,4);
e=test1(:,5);
f=test1(:,6);

fmt = {'*','o','^','.','+','x','s','p','h'};
 
f = 0;
for n = 1:3
scatter(a(n),b(n),['r' fmt{f+1}], 'Linewidth',15);
hold on;

scatter(c(n),d(n), ['b' fmt{f+2}], 'Linewidth',15);
hold on;

scatter(e(n),f(n), ['g' fmt{f+3}], 'Linewidth',15);
hold on;
f = f + 3;
end

xlim ([0.8 1.3]);
ylim([100 180]);
set(gca,'Fontsize',24,'Linewidth',2);
grid;

Answer 2

[Adam Danz]

"I want to plot each "9 dots" in the graphic with different markers."

Use group-scatter gscatter(x,y,g,clr,sym,siz).

Each coordinate will be its own group but it's color will be defined by an additional grouping variable. Since gscatter() returns a handle for each group, you can change the marker for each coordinate. See inline comments for more detail.

% Your raw data; an nxm matrix where every 2 columns define (x,y) coordinates
% for a particular group (even number of columns)
%test1 = randi(10,3,6);  %fake data
load -ascii test1.txt;   % Your actual data

% Reshape the data into (x,y) pairs (2 columns) and identify the groups for 
% each coordinate
test1xy = reshape(test1',2,numel(test1)/2)'; %[x,y] columns
test1Grp = repmat((1:(size(test1,2)/2))',size(test1,1),1);  %groups

% set group colors
color = hsv(size(test1,1));
color = color(test1Grp,:); 

% Plot the data so that each coordinate gets its own handle and each group
% gets it's own color
gsh = gscatter(test1xy(:,1), test1xy(:,2), 1:size(test1xy,1), color, '.', 15, false);

% Set markers
markers = {'s' '^' 'p' 'h' 'v' 'd' 'x' 'o' '+'};  %must match number of groups!
set(gsh,{'Marker'}, markers(:))

% fill markers 
set(gsh,{'MarkerFaceColor'}, mat2cell(color,ones(size(color,1),1),3))

Results (from your data)

Answer 3

[dpb]

"plot each "9 dots" in the graphic with "different marker.". Not each group."

Wow. But, ok...that's simpler with plot than it is with scatter owing to weakness in the implementation of the scatter plot...it's designed for groups and can only accept vector, not array inputs, sadly.

mkrs = {'*','o','^','.','+','x','s','p','h'}.';   % NB: column, NOT row
x=test1(:,1:2:end);                               % convenient shorthand 
y=test1(:,2:2:end);                               % variable names
x=x(:).'; y=y(:).';                               % turn into row vectors
dmy=nan(size(x));                                 % a placeholder to fool plot()
hL=plot([x;dmy],[y;dmy],'.','markersize',15);     % create the line, default marker
set(hL,{'Marker'},mkrs)                           % and set the markers to the list

The above also has to have a workaround to avoid the use of looping or arrayfun() to add multiple individual points to the plot. For arrays, plot creates a line for each column; but it ignores orientation if the input is a vector and only creates a single line handle. We need one for each point here to set the marker individually so the NaN dummy vector creates the non-showing data to pass an array so hL will be an array of line handles.