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Mathematical expressions

The following expression elements are available:

• Infix (dyadic) operators: + - * / ^

• Prefix (monadic) operators: + -

• Functions: sin, cos, tan, asin, acos, atan, sqrt, log, log10, exp

• Constants: pi, e, root2, root3

• Units: m, cm, mm, yd, ft, ', in, ", deg, rad

NormalThe vector that is perpendicular to a flat plane at the selected point. In the case of a non-flat plane, the vector that is perpendicular to the plane tangent to the surface at the selected point. precedence rules apply:

1 + 2 * 3 ^ 4 = 1 + (2 * (3 ^ 4)) = 163

Parentheses are required for expression arguments and optional for simple arguments:

• sqrt 2 = sqrt(2) = 1.4142...

• sqrt 2*2 = (sqrt 2) * 2 = 2.8284...

• sqrt(2*2) = 2

Missing operators are inferred:

• 1 1/2 = 1 + 1/2

• 1’6” = 1’ + 6”

• 1ft 6in - 17in = 1ft + 6in - 17in

• 1 2 3 4 5 = 1 + 2 + 3 + 4 + 5 = 15

• (1)(2)(3)(4)(5) = (1) * (2) * (3) * (4) * (5) = 120

• 2(1 + 2) = 2 * (1 + 2) = 6

• sqrt 2 sqrt 2 = sqrt 2 * sqrt 2 = 2

• 4(4atan(1/5) - atan(1/239)) = 4 * (4 * atan(1/5) - atan(1/239)) = pi

Units are applied to previous terms if units were not specified and are applied to subsequent terms unless you override them:

• 1 + 1cm = 1cm + 1cm

• 1cm + 1 = 1cm + 1cm

• 1cm + 1 + 1mm = 1cm + 1mm + 1mm

• 1cm + 1 1/2 mm = 1cm + 1mm + 1mm / 2

Trigonometry functions work in radians by default, but you can enter degrees:

sin(45 deg)

Numbers support standard form, but e is a built-in constant:

• 2e2 = 200
  2e 2 = 2 * e * 2 = 10.873...

• 2e-2 = 0.02
  2e – 2 = 2 * e – 2 = 3.436...

• 2e1 = 20
  2e = 2 * e