Setting marker and colour in gscatter by the categorical group string

I have datasets that will always have a category attached (species of animal) and I want to be able to define that each species has a different marker type. I will likely use this to also set the colour by a second group – the site from where the animals came.

I have seen code for having Matlab use a different colour for each group, but not a different marker.

More importantly, I want to be able to define these so they are always the same (cattle are always circles and horses are always squares, etc).

Answer 1

[Subhadeep Koley]

Hi, you can refer to the example code below, which plots the height and weight of various animals grouped by species and country of origin. (Use the attached demoDataMultiScattered.mat file)

% Load the demo data
load demoDataMultiScattered.mat;
% Create grouping variable 'g'
g = {country, species};
% Declare colors and markers
colors = 'rgbcmyk'; markers = 'hsdp';
% Plot the data
figure('Color','w'); 
gscatter(height,weight, g,colors,'hsdp',8);
legend('Location','northeastoutside');
title('Multi Grouped Scatter Plot');
xlabel('Height (in cm)');
ylabel('Weight (in Kilograms)');

Hope this helps!

Answer 2

[Derek Hamilton]

Thank you for this.

I am hoping to do something a bit more complex, though the more I read I am thinking it may require plotting via a loop.

What I want is for say Asia to always be Green and Canada to always be Red, and Reptiles to always be Stars and Mammals to always be Squares, rather than Matlab setting the Marker and Color in order that the Group first appears in the data.

However, as I am realising I may need to Sort the data initially if I use gscatter or use a loop and just create a normal xy plot.

[Subhadeep Koley]

Yes you can use loop. But plotting using a loop is inefficient. As, it generates a huge number of individual graphic objects instead of just one. You can do that without using any loop also.

Refer the code below

% Load the demo data
load demoDataMultiScattered.mat;
% Create grouping variable 'g'
g = {country, species};
% Declare colors and markers
colors = 'rrrrggggbbbbmmmm'; markers = 'hsdp';
% Plot the data
figure('Color','w'); 
gscatter(height,weight, g, colors, markers, 8);
legend('Location','northeastoutside');
title('Multi Grouped Scatter Plot');
xlabel('Height (in cm)');
ylabel('Weight (in Kilograms)');

Hope this helps!

[Marcus Leiwe]

I realise this is jumping on an old question but what if in one of the cases that group is now empty. I find that gscatter is exluding the group