How to plot a part of an array?

lets say i have

x = 1:20

and i have this eqution;

y = 2x+3

how to plot (x,y) where x only goes up to 10 while the whole 20 numbers are still avalible on the plot, just as empty space?

In another words i want to adjust the size of my x axis and y axis without it being automatically adjusted by Matlab.

Answer 1

[Manikanta Aditya]

Hi, check this:

% Create the x vector
x = 1:20;

% Calculate y based on the equation
y = 2 * x + 3;

% Create a figure and plot the data
figure;
plot(x, y);

% Set the x-axis limits to display the full range of 1 to 20
xlim([1 20]);

% Add labels and a title
xlabel('x');
ylabel('y');
title('Plot of y = 2x + 3');

Thanks!

[Ahmed]

I Appreciate your help but that is not what i intended.

I want the full numbers displayed but the graph itself (the blue line) to stop at x = 10, not to go to the end of the graph if you catch my meaning.

[Manikanta Aditya]

Okay, you want like this right?

x = 1:20;
y = 2*x + 3;

% Plot only the first 10 points
plot(x(1:10), y(1:10), 'b'); % 'b' specifies blue color

% Hold on to the current plot
hold on;

% Set the limits for x and y axes
xlim([1 20]);
ylim([min(y) max(y)]);

% Label the axes
xlabel('x');
ylabel('y');

% Give the plot a title
title('Plot of y = 2x + 3');

% Release the hold on the plot
hold off;

[Ahmed]

YES Exactly !

Thank you so much.

[Manikanta Aditya]

Even this is another way of representation, hope this helps you.

% Create the x vector
x = 1:20; 

% Calculate y based on the equation for x values up to 10
y = 2 * x(1:10) + 3;

% Create a figure and plot the data
figure;
plot(x(1:10), y, 'LineWidth', 2); 
hold on; 

% Add remaining x-axis ticks without plotting data points
plot(x(11:end), nan(1,10), 'x', 'Color', [0.5 0.5 0.5]); 

% Set the x-axis limits to display the full range of 1 to 20
xlim([1 20]); 

% Add labels and a title
xlabel('x');
ylabel('y');
title('Plot of y = 2x + 3');

[Manikanta Aditya]

Your Welcome @Ahmed!

[Ahmed]

I always felt that graphs in matlab are tricky. But i started to understand how to do this.

Appreciate it mate.

[Manikanta Aditya]

Great to hear, Hope you become proficient soon :)