Exam 1 Results
30
Percent of Scores
25
20
Mean
Median
Mode
St Dev
Minimum
Maximum
62
63
72
14
24
90
15
10
5
0
<40
40-49
50-59
60-69
Score Range
Engr 0012 (04-1) LecNotes 18-01
70-79
80-90
Contrasting MATLAB with C
MATLAB
C language
Workspace - interactive
computation
No real equivalent
script - program control
algorithm
main - program control
function/algorithm
functions - perform specific
computation or task
functions - perform specific
computation or task
Engr 0012 (04-1) LecNotes 18-02
Contrasting variables
MATLAB
C language
Two variable types
You must decide type based
upon need and use
double precision, complex
string (text)
Use meaningful names
Engr 0012 (04-1) LecNotes 18-03
int (+/-32,000)
log int (+/- 2 billion)
float (8 digits ~ 10+/-37)
double (16 digits ~ 10+/-307)
char (ASCII character)
Use meaningful names
I/O Commands
MATLAB
C language
% comment delimiter
// comment delimiter
input get info from
keyboard
scanf get info from
keyboard
fprintf display info to
screen
printf display info to
screen
load read file into memory
no equivalent command - must
define a function to do this
Engr 0012 (04-1) LecNotes 18-04
decision (branching) structures - if/elseif
MATLAB
if ( )
action1;
action2;
elseif ( )
action3;
else
action4;
action5;
end %if
end terminates
structure
Engr 0012 (04-1) LecNotes 18-05
C language
suppresses
display
if (
{
)
action1;
action2;
}
else if ( )
{
action3;
}
else
{
{ } used to enclose
action4;
actions that belong
action5;
together
}
ends
statement
decision (branching) structures - switch/case
MATLAB
C language
switch (value)
case {1, 3}
action1;
action2;
case {4}
action3;
otherwise
action4;
action5;
end %switch/case
switch (value)
{ // begin switch
case 1:
case 3: action1;
action2;
break;
case 4: action3;
break;
default: action4;
action5;
} //end switch
end terminates
structure
{ } used to enclose
actions that belong
together
Engr 0012 (04-1) LecNotes 18-06
repetition (looping) structures - for loop
MATLAB
C language
% initialize loop sum
sum = 0;
// initialize loop sum
sum = 0;
% add first N numbers
for (k=1:1:N)
sum = sum+k;
end % for
// add first N numbers
for (k=1;i<N+1;k=k+1)
{
sum = sum+k;
} //end for
end terminates
structure
{ } used to enclose
actions that belong
together
Engr 0012 (04-1) LecNotes 18-07
repetition (looping) structures - while loop
MATLAB
C language
% initialize loop sum
sum = 0;
k = 1;
// initialize loop sum
sum = 0;
k = 1;
% add first N numbers
while (k<N+1)
sum = sum+k;
k = k+1;
end % while
// add first N numbers
while (k<N+1)
{
sum = sum+k;
k = k+1;
} //end while
end terminates
structure
{ } used to enclose
actions that belong
together
Engr 0012 (04-1) LecNotes 18-08
repetition (looping) structures - do..while loop
MATLAB
C language
no do..while
// initialize loop sum
sum = 0;
k = 0;
// add first N numbers
do
{
k = k+1;
sum = sum+k;
} while (k<N)
Engr 0012 (04-1) LecNotes 18-09
sample C-program
/*
Your Name(s)
Engineering 12, Fall Term 2002
Class Activity 18-1
*/
// include libraries
#include <stdio.h>
preprocessor
commands
declaration
section
// prototypes
void displayheader( void );
//********************************************************
main()
Engr 0012 (04-1) LecNotes 18-10
sample C-program
use easily seen
marker to separate
functions
function begin/end
enclosed by { }
placeholders correspond to
variable type
//********************************************************
main()
{ // begin main
// variable declarations
int first;
double second;
char letter;
variable declaration section
for main
displayheader();
command to display header
// algorithm
printf( "\nPlease enter an integer ==> " );
scanf( "%d", &first );
printf( "\nPlease enter a real number ==> " );
scanf( "%lf", &second );
printf( "\nPlease enter a character ==> " );
fflush( stdin );
scanf( "%c", &letter );
fflush( stdin );
& address of
operator
printf( "\n\nYou entered the integer %d "
" \n
the real number %lf "
" \n
and the character %c \n\n",
first, second, letter );
return(0);
} // end main
Engr 0012 (04-1) LecNotes 18-11
//********************************************************
void displayheader( void )
sample C-program
needs nothing
returns nothing
//********************************************************
void displayheader( void )
/*
purpose: display header info to screen
goal state: header info on screen
*/
{ // begin displayheader
printf(
printf(
printf(
printf(
printf(
"Your name(s)" );
"\nEngineering 12, Fall Term 2003" );
"\nClass Activity 18-1 \n" );
"\n\nThis program performs simple I/O operations" );
"\n" );
} // end displayheader
Engr 0012 (04-1) LecNotes 18-12