How do I change File Name Variable within a Loop

Looked at sprintf() and did not understand it. Keep it simple, I do not understand code, this is for a uni assignment, prof expects us to "just google it" when we run into issues

Trying to load 12 files. Names are "Ss_R_L.mat" where

s is a number between 1 and 3

R is either "Walk" or "Run"

L is either "90PSL" or "PSL"

for R = 1:2
    if R == 1
        % use "Walk"
    else
        % use "Run"
    end
    
    for L = 1:2
        if L == 1
            % use "PSL"
        else
            % use "90PSL"
        end
        
        for S = 1:3
            if S == 1
                load('S1_R_L.mat')
            elseif S == 2
                load('S2_R_L.mat')
            else
                load('S3_R_L.mat')
            end
            
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
            %% Plotting Data from the Files %%
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
        end
    end
end

Answer 1

[Hiroki Okawa]

for R = 1:2
    if R == 1
        txt_R = 'Walk';
    else
        txt_R = 'Run';
    end
    for L = 1:2
        if L == 1
            txt_L = 'PSL';
        else
            txt_L = '90PSL';
        end
        for S = 1:3
            filename = ['S', num2str(S), '_', txt_R, '_', txt_L, '.mat']
            load(filename)            
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
            %% Plotting Data from the Files %%
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
        end
    end
end

or

Rs = {'Walk', 'Run'};
Ls = {'PSL', '90PSL'};
for r = 1 : 2
    for l = 1 : 2
        for s = 1 : 3
            filename = ['S', num2str(s), '_', Rs{r}, '_', Ls{l}, '.mat']
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
            %% Plotting Data from the Files %%
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
        end
    end
end

[Emily Dueck]

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