How to loop through multiple text files and make plot for each one in a single script?

I have 5 text files that have the same exact variables and column formats. The txt. files are named a1.txt, a2.txt, etc. I have a script that solves for a velocity value as every x coordinate in the txt file. I would like to run all 5 txt files and then plot their different velocity function into one figure, so that I can compare. Here is the code I have so far:

%Open and read txt file
fid = fopen('Test.txt','rt');
fgetl(fid);
data = fscanf(fid,'%f',[7, Inf]);

%Grab variables from txt file
s = data(:,1);
x = data(:,2);

%Calculating V
%EXAMPLE EQUATION

v = 2*s 

figure
plot(x,v,'Color',[0,0.7,0.9])
title('Test Plot')
xlabel('x')
ylabel('v')

Now what I would like to do is create a loop that reads 5 txt files in my directory, then create 5 different plots within 1 figure

Answer 1

[KSSV]

txtFiles = dir('*.txt') ;
N = length(txtFiles) ; 
figure
hold on
for i = 1:N
    %Open and read txt file
    fid = fopen(txtFiles(i).name,'rt');
    fgetl(fid);
    data = fscanf(fid,'%f',[7, Inf]);

    %Grab variables from txt file
    s = data(:,1);
    x = data(:,2);

    %Calculating V  
    %EXAMPLE EQUATION

    v = 2*s 

    
    plot(x,v)
end
title('Test Plot')
xlabel('x')
ylabel('v')
legend

[Andrew Lackey]

Error for this line:

fid = fopen(txtFiles)i).name,'rt');

The error reads:

File: A1Code.m Line: 11 Column: 26

Invalid expression. Check for missing multiplication operator, missing or unbalanced delimiters, or other syntax

error. To construct matrices, use brackets instead of parentheses.

[KSSV]

It is a typo error..... edited the code.

[Andrew Lackey]

Thank you, it works perfectly! How can I make each plot a different color? And add a legend?

[KSSV]

You can save the data into array and use your required color. Read about legend to give your required names.

[Andrew Lackey]

Thank you!