Chapter 1 : An Overview of Matlab

Question 1

clear the command window

Answer 1

clc

Question 2

removes all variables from memory

Answer 2

clear

Question 3

removes the variable var1 and var2 from memory

Answer 3

clear var1 var2

Question 4

lists the variables currently in memory

Answer 4

who

Question 5

lists the current variables and sizes and indicates if they have imaginary parts

Answer 5

whos

Question 6

generates an array with regularly spaced elements

Answer 6

:

colon

Question 7

separates elements in an array

Answer 7

,

comma

Question 8

suppresses screen printing: also denotes a new row in an array

Answer 8

;

semi colon

Question 9

continues a line

Answer 9

…

ellipsis

Question 10

to simultaneously delete (kill) the end of the line

Answer 10

Ctrl k

Question 11

infinity

Answer 11

Inf

Question 12

indicates an undefined numerical result

Answer 12

NaN

Question 13

show 4 decimal places

Answer 13

format short

Question 14

show 16 digits

Answer 14

format long

Question 15

five digits (four decimals) plus exponent

Answer 15

format short e

Question 16

16 digits (15 decimals) plus exponent

Answer 16

format long e

Question 17

two decimal digits

Answer 17

format bank

Question 18

rational approximation (43/7)

Answer 18

format rat

Question 19

suppresses some blank lines

Answer 19

format compact

Question 20

resets to less compact display

Answer 20

format loose

Question 21

e^x

Answer 21

exp(x)

Question 22

ln(x)

Answer 22

log(x)

Question 23

log base 10 x

Answer 23

log10(x)

Question 24

arc sin, cos, tan

Answer 24

asin(x), acos(x), atan(x)

Question 25

sin in degrees

Answer 25

sind(x)

Question 26

puts grid lines on a plot

Answer 26

grid

Question 27

enables placement of text with the mouse

Answer 27

gtext(‘text’)

Question 28

generates a plot of the array y versus x on rectilinear axes

Answer 28

plot(x,y)

Question 29

puts text in a title at the top of the plot

Answer 29

title(‘text’)

Question 30

adds text to the horizontal axis

Answer 30

xlabel(‘text’)

Question 31

adds text to the vertical axis

Answer 31

ylabel(‘text’)

Question 32

designates a comment

Answer 32

%

Question 33

displays the contents, but not the name, of the array A

Answer 33

disp(A)

Question 34

displays the text string enclosed within single quotes

Answer 34

disp(‘text’)

Question 35

displays the text in quotes, waits for user input from the keyboard, and stores the value in x

Answer 35

x = input(‘text’)