Epsilon doc

[zeffii]

Epsilon for arithmetic precision needs a canonical document, it is used in several nodes. Some notes here regarding user configurable epsilons. This is a chance to use a consistent explanation for this precision/tolerance parameter.

Epsilon is hard coded in these nodes:

• nearest point on mesh
• raycaster lite
• object_nodes\points_from_uv_to_mesh
• spatial\random_points_on_mesh
• ...more

Epsilon n is described as some formulation of 1 / 10 ** self.epsilon:

• edges intersect mk3 (range is 3 significant digits to 5..)
• merge mesh 2d lite , this parameter is called "accuracy" (range from 3 to 12)
• modifier_make\fractal_curve
  • here self.precision is the controllable parameter. epsilon = 10 ** (- self.precision)
  • min=0, max=10, default=7
  • helpful description "decimal precision of coordinates for calculations"
• spatial\delaunay_2d_cdt
  • default=5, min=3, max=12,
  • description: For nearness tests; should not be zero
• surface\adaptive_tessellate ,called accuracy
  • default=5, min=3, max=12,
  • description='Some errors of the node can be fixed by changing this value'
• surface\tessellate_trim: called accuracy
  • epsilon = 1.0 / 10**self.accuracy
  • default=5, min=3, max=12,
  • description='Some errors of the node can be fixed by changing this value'

other property names or descriptions using Epsilon:

• curve\rbfCurve , epsilon (range 0.0 to 1.0)
  • affecting shape of a produced Curve
• field\mesh_surface_field , epsilon (range 0.0 to 1.0)
  • Epsilon parameter of used RBF function; it affects the shape of
    generated field. The default value is 1.0
• field\minimal_sfield and field\minimal_vfield
  • it affects the shape of generated field. The default value is 1.0.
• generators_extended\triangle called "Tolerance"
  • for remove doubles (no max, no min default 1e-6)
• logic\neuro_elman.py
  • coefficient participates in the learning assessment function
• surface\interpolating_surface and surface\min_surface_from_curve
  • default = 1.0, min = 0.0,
  • epsilon is a socket, The docs do not cover it.
  • scipy.interpolate.Rbf
    • Epsilon: Adjustable constant for gaussian or multiquadrics functions - defaults to approximate average distance between nodes
• surface\minimal_surface
  • default = 1.0, min = 0.0,
  • docs: Epsilon parameter of used RBF function; it affects the shape of generated surface. The default value is 1.0.
  • ( still is the same as scipy.interpolate.Rbf )