CIM4305 Computer Aided Analysis

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CIM4305 Computer Aided Analysis

• Week 3 - Script M-files

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Last Week

• Plotting 2D and 3D Graphs
• Adding Titles and Labels
• Setting Properties
• Line style Colour and Markers
• Controlling the axis
• Multiple Plots
• Useful commands
• Figure Hold on Hold off Close all Figure

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This Week

• Script M-files
• Commenting
• Current Working Directory

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Script M-files

• Typing at the command window can become slow and
  inefficient
• Re-evaluating a large number of commands
• Wish to change variables
• Script files allow any number of commands to be
  run by only typing the name of the file at the
  command window
• gtgt example1

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Script M-files

• Can be saved to disk!!

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Opening a new script file

• File gt New gt M-file
• Click on the blank page icon

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Naming Files

• Choose a name that helps you remember what the
  file does
• The script file can be called from the command
  window using this name
• Whilst names can contain numbers the first
  character MUST be a letter.

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Adding Comments

• Helps you and other people understand your code
• Short description of what the file does
• When was it created and who by?
• Have there been any modifications?
• Add comments to key parts of the code
• GET INTO THE HABIT!!

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Current Working Directory

• Matlab is only able to see files in the
  directory it has been set to use
• Important to be able to direct Matlab to where
  you work is stored
• Default CWD is C\Matlab\work
• Not always a good choice to save work there
• On University machines this directory is wiped
  when you logout!

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Seeing your CWD

• To see which directory Matlab has as its CWD type
• gtgt pwd
• Print Working Directory

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Changing you CWD

• At the command prompt type the full address of
  the directory you wish to use
• gtgt cd K\MatlabWork
• OR, select the icon positioned to the right of
  the CWD window, and choose the directory you wish
  to use

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Running a script file

• Type the file name directly into the command
  prompt
• gtgt Example1

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This Week

• Work through Exercise 3
• Use Notes 2 to help you