Need help.... How to plot sequences

Hello,

I have a report due in two days and have no idea how to plot this sequence. I know almost nothing about Matlab and my tutors as usual have been no help at all.

If some one can help me out here I would greatly appriciate it.

The sequence is:

𝑥(𝑛) = {… , 5, 4, 3, 2, 1, 5, 4, 3, 2, 1, 5, 4, 3, 2, 1, … }

Cheers

[Mario van Rooij]

Where does the n come into play? What do you want to plot when n = 10 for example?

[Connor Wright]

I want to plot −20 ≤ 𝑛 ≤ 12.

Answer 1

[Star Strider]

The mod function and the colon,: operator are your friends!

[Connor Wright]

How would I implement the mod function?

[Star Strider]

Example —

x = 0:30;
y = mod(x, 15);

figure
plot(x, y)
grid

I leave the rest to you!

[Connor Wright]

Right first off thank you for putting me on the right path, however I have staryed off it and went down a different route and have run into trouble. my code is below and I keep getting the sam error of 'error using plot vectors must be the same length'

n = -20:12
x = repmat([5,4,3,2,1],3,15)
linspace = x
plot(n,x)
Error using plot
Vectors must be the same length

Any ideas?

[Star Strider]

Use the colon operator with the ‘n’ vector, and then operate on it to create the triangular pulses.

That will eliminate the vector length problem.

[Connor Wright]

I really am sorry about this but I dont understand what you mean.

[Star Strider]

Please experiment!

Use my example as a guide, and carefully read the documentation for colon. Note how to use it to code a descending sequence.