Finding the frequency spectrum of a list of column data

I am very new to MATLAB. Teaching myself as I go for my course.

I am given raw data of monthly averages of magnetic field intensity of the earth over a long period of time. Given 582 months worth of data,

I am to plot the data, then using a sampling rate of 12 beginning at t=0 I am to compute the spectrum. the sample frequency is 12 because we are looking at annual variations

Answer 1

[AndresVar]

Here are three options

1) My favorite is to use pspectrum(data,fs). Where fs is sample frequency.

For more information 'doc pspectrum'

2) You can also use the signal analyzer app to analyze and generate the code.

3) You can use FFT to get power spectum see example: Power Spectral Density Estimates Using FFT - MATLAB & Simulink (mathworks.com)