Variables

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• Questions?
• Variables (and Related Ideas)
  • Sections 3.1 through 3.7
    • Review of lots we’ve already done (e.g., up arrow)
    • Math constants: pi, i, j, etc.
    • Variable naming rules (e.g., start with letter)
    • Types of variables, e.g., characters, real numbers, integers
      • Or types of data
      • Example of one operation that makes sense and one that doesn’t
        • 2 * pi
        • 'a' * 'b'
      • Different types imply different operations
  • Examples / questions
    • Exam question asking for code that demonstrates difference between Matlab and math variables
      

      x = 3
      x = x + 1

    • What are Matlab and math variables abstractions of, respectively?
      • Matlab: abstraction of memory location
        • = is directional!
          • x = 1 stores 1 into x
          • 1 = x error
      • Math: abstractions of values
        • x + y = y + x is a meaningful statement about all numbers
    • Assign some strings to variable(s)
      

      >> name = 'Jill Smith'
      name =
      Jill Smith
      >> name
      name =
      Jill Smith
      >> 'name'
      ans =
      name

• Lab 1
• Next
  • Scripts
    • Read sections 4.1 through 4.2
  • Counting and expected value for lab
    • Watch videos described in lab handout

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