chapter 9: mupad programming ii procedures matlab for scientist and engineers using symbolic toolbox
TRANSCRIPT
Chapter 9:
MuPAD Programming IIProcedures
MATLAB for Scientist and Engineers
Using Symbolic Toolbox
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You are going to See that MuPAD provides built-in editor for
programming Implement simple MuPAD procedures Use local variables inside the procedures Handle variable number of arguments to pro-
cedures
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Using MuPAD Editor
Invoking MuPAD Editor
Auto-indentation: TAB Comments: //, /* .. */
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Bookmarks
Add Bookmarks
Go to the Bookmark Delete all Bookmarks
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Creating a Procedure
proc - procedure
Name of the procedure
Body
Suppress the procedure definition message
or just end
or just end
factorial.mu
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Using the Procedure
Read-in the MuPAD file.factorial.mu
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Return Value
By default, a procedure returns the result of the last executed command.
Use the return command for other results.
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Returning Multiple Results
Any MuPAD object can be returned.
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Exercise
Implement a procedure maximum(a, b) re-turning the maximum value of two arguments.
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Local Variables
You can declare an arbitrary number of local variables by specifying a sequence of identi-fiers after local keyword.
If you don't use local keyword for a vari-able, it becomes global variable.
Local Variable
DO NOT FORGET to initialize all the local variables!
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Global Variables
Do not use Global Variables! If you must, save it first.
To use more decimal digits inside the procedure.
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Default Values for Arguments
You can give a default value for an argument.
default value
with argument
without argument
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error Function
Aborts with the message.
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Sub-procedure
Local procedure inside a procedure
g() is visible only inside this procedure.
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Type Declaration
Specify the type of input argument
Accepts only non-negative integers.
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Variable Number of Arguments
System function max
Accessing arguments
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Simulating System Function max
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Var. No. of Args : More Examples
You may use both formal parameters and ac-cesses via args in a procedure:
Returns itself symbolically.
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Exercise
Write a short procedure date that takes three integers month, day, year as input and prints the date in the usual way. For example, the call date(5, 3, 1990) should yield the screen output 5/3/1990.
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Exercise
We define the function f : N → N by
The “(3 x + 1) problem” asks whether for an arbi-trary initial value x0 ∈ N, the sequence recur-sively defined by xi+1 := f(xi) contains the value 1. Write a program that on input x0 returns the smallest index i with xi = 1.
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option noExpose
You can hide your code and publish it.
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Start Debugging
Menu Notebook Debug
Command
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Debug Control
Step Over
Step Into
Step Out
Continue
Toggle Breakpoint
Watch
Evaluate
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Modifying Source
File New Editor …
Re-read the file or
Copy & Paste
to the Notebook.
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Key Takeaways
Now, you are able to use MuPAD editor for writing your procedures, implement simple procedures and specify return
values deal with the variable number of arguments perform type checking on the input arguments. and debug your procedures.
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Notes
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Notes
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Notes