SE207 Lab 2

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SE207 Lab 2

• Objective
• To be able to create script and function files

2
MATLAB Files

• Two types of files
• SCRIPT files
• FUNCTION files
• Both have the extension .m M-files
• (file1.m, f2.m)

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M-files

• SCRPT Files
• a list of MATLAB instructions
• saved on a file for convenience
• no input argument
• The variables are global

• FUNCTION files
• Starts with FUNCTION statement that specifies
  the input and output arguments
• Local variables
• Treated as the built-in functions

t00.110 ysin(t) plot(t,y)
function yfplot2(t) ysin(t) plot(t,y)
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Function M-files

• create an m-file and save it as fplot.m

FILE
New
M-file
function yfplot(t) ysin(t)
Open
M-file

• MATLAB Command Window

gtgt t00.110 gtgt zfplot(t) gtgt plot(t,z)
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MATRIX OPERATIONS

• Transpose A
• inverse inv(A)
• determinant det(A)
• rank rank(A)

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Special functions

• Exponential exp(x)
• square root sqrt(x)
• natural logarithm log(x)
• common logarithm log10(x)
• absolute value abs(x)

more
details Use help to know
related functions
7
If structures

• General form
• If condition
• statements
• else
• statements
• end

If (xgt0) fx2 else f0 end
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for loops

• General form
• for indexinitial increment limit
• statements
• end
• special case
• if increment is 1
• for indexinitial limit

for i1100 x(i)sin(i.2) end