Vectors

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• Questions?
• Introduction to Matlab Vectors
  • Sections 2.1.1 and 2.2
    • How to write vectors
      • Square brackets w/ elements
      • Colon w/ range
        • first : step : last
        • first : last
    • Indices for accessing individual elements, both to read value and for assignment
      
    • Arithmetic with vectors, e.g., sum, max, min, prod, cumsum, cumprod
    • Multiplying vectors is different from multiplying matrices
      

      v1 = [ 7 3 19 -6]
      v1 =
           7     3    19    -6
      v2 = 1:4
      v2 =
           1     2     3     4
      sum( v1 )
      ans =
          23
      v1 + v2
      ans =
           8     5    22    -2
      v1(2)
      ans =
           3
      v1(2) = 103
      v1 =
           7   103    19    -6
      ones( 1, 5 )
      ans =
           1     1     1     1     1
      ones(1,2)
      ans =
           1     1
      ones(1,2) * 2
      ans =
           2     2
      [ones(1,5) 2 2 3 4]
      ans =
        Columns 1 through 8
           1     1     1     1     1     2     2     3
        Column 9
           4

  • Lesson 2
    • Grade and category vectors
    • Maximum grade
    • Comparison operators:
      

      x = 4
      x =
           4
      y = 17
      y =
          17
      x == y
      ans =
           0
      x == 4
      ans =
           1
      x < y
      ans =
           1
      x <= y
      ans =
           1
      x ~= y
      ans =
           1
      v1
      v1 =
           7   103    19    -6
      v1 == 19
      ans =
           0     0     1     0
      v2
      v2 =
           1     2     3     4
      v2 < v2
      ans =
           1     1     1     0

• Next
  • Logical vectors and logical operations
  • Sections 1.6 and 2.5

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