# 4.8.1: Plotting Vectors Additional Material

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Watch this video on making an x-y plot with vectors. It also shows how to plot 2 curves on 1 figure with "hold on".

MATLAB Function Plotting Basics, Robert Talbert

Important note:

When a function has more than 1 input, you must put commas between the inputs.

Even though you can leave-out commas when specifying a vector such as x = [1 2 5 8], this does not work for functions. The commas between the inputs are required.

Examples:

plot(x, y), not plot(x y)

plot(x, y, '*'), not plot(x y '*')

.

Additional MATLAB functions for labeling plots:

title() puts a title on a plot. The argument of title is a character string.

Examples:

title('sin(x) vs. t')

xlabel() and ylabel() put labels on the x and y axes of a plot.

Examples:

xlabel('Time (s)')

ylabel('Distance')

##### Exercise $$\PageIndex{1}$$ Voltage_Vector

(1 pt) Create a Matlab script: voltage_vector_YourName.m
(1 pt) Clear any variables; close any figures; eliminate white space; clear the console
clear all; close all; format compact; clc;
%% V = IR
(2 pts) Create a vector I (current) from 0 to 15 amps in steps of 3 amps
(2 pts) Create a vector R (resistance) from 100 to 600 Ohms in steps of 100 Ohms
(2 pts) Compute the corresponding vector of voltages by multiplying I time R element-wise with this code
V = I.*R % (volts)
%% Plot
% (1 pt) Open a figure window
% (1 pt) Plot V (y-axis) vs. I (x-axis) with this code:
plot(I, V, '-o')

title('Voltage vs. Current')
% (1 pt) Label the x-axis with this code:
xlabel('I (amps)')
% (1 pt) Label the y-axis with this code:
ylabel('V (volts)')