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Vectors

• veczero - Returns the zero vector, {0 0 0}

  Example:vmd > veczeroInfo) 0 0 0

• (C++) vecadd v1 v2 [v3 ... vn] - Returns the vector sum of all the terms.

  Examples:vmd > vecadd {1 2 3} {4 5 6} {7 8 9} {-11 -11 -11}Info) 1 4 7vmd > vecadd {0.1 0.2 0.4 0.8} {1 1 2 3} {3 1 4 1}Info) 4.1 2.2 6.4 4.8vmd > vecadd 4 5Info) 9

• (C++) vecsub v1 v2 - Returns the vector subtraction of the second term from the first

  Examples:vmd > vecsub 6 3.2Info) 2.8vmd > vecsub {10 9.8 7} {0.1 0 -0.1}Info) 9.9 9.8 7.1vmd > vecsub {1 2 3 4 5} {6 7 8 9 10}Info) -5 -5 -5 -5 -5

• (C++) vecscale c v -
• (C++) vecscale v c - Returns the vector of the scalar value c applied to each term of v

  Examples:vmd > vecscale .2 {1 2 3}Info) 0.2 0.4 0.6vmd > vecscale {-5 4 -3 2} -2Info) 10 -8 6 -4vmd > vecscale -2 3Info) -6

• vecdot v1 v2 - Returns the scalar dot product of the two vectors

  Examples:vmd > vecdot {1 -2 3} {4 5 6}Info) 12vmd > vecdot {3 4} {3 4}Info) 25vmd > vecdot {1 2 3 4 5} {5 4 3 2 1}Info) 35vmd > vecdot 3 -2Info) -6

• veccross v1 v2 - Returns the vector cross product of the two vectors.

  Examples:vmd > veccross {1 0 0} {0 1 0}Info) 0 0 1vmd > veccross {2 2 2} {-1 0 0}Info) 0 -2 2

• veclength v - Returns the scalar length of v (
  
  )

  Examples:vmd> veclength 5Info) 5.0vmd > veclength {5 12}Info) 13.0vmd > veclength {3 4 12}Info) 13.0vmd > veclength {1 -2 3 -4}Info) 5.47723

• veclength2 v - Returns the square of the scalar length of v (
  
  )

  Examples:vmd > veclength2 5Info) 25vmd > veclength2 {5 12}Info) 169vmd > veclength2 {3 4 12}Info) 169vmd > veclength2 {1 -2 3 -4}Info) 30

• vecnorm v - Returns the vector of length 1 directed along v

  Examples:vmd > vecnorm -10Info) -1.0vmd > vecnorm {1 1 }Info) 0.707109 0.707109vmd > vecnorm {2 -3 1}Info) 0.534522 -0.801783 0.267261vmd > vecnorm {2 2 -2 2 -2 -2}Info) 0.408248 0.408248 -0.408248 0.408248 -0.408248 -0.408248

• vecdist v1 v2 - Returns the distance between the two vectors (
  
  )

  Examples:vmd > vecdist -1.5 5.5Info) 7.0vmd > vecdist {0 0 0} {3 4 0}Info) 5.0vmd > vecdist {0 1 2 3 4 5 6} {-6 -5 -4 -3 -2 -1 0}Info) 15.8745

• vecinvert v - Returns the additive inverse of v (
  
  v).

  Examples:vmd > vecinvert -11.1Info) 11.1vmd > vecinvert {3 -4 5}Info) -3 4 -5vmd > vecinvert {0 -1 2 -3}Info) 0 1 -2 3

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