superEllipseProfileType

complexType · extension complexBaseType · all

Superellipse composed of an upper and a lower half

The profile consists of an upper and a lower semi-superellipse, which meet at their widest point on the line z = z0 and can be shaped independently. Width and total height are always 1, and the profile is centered at the origin. lowerHeightFraction is the height of the lower half relative to the total height and thus defines where the two halves meet. Order and curve parameter are described for standardProfileType.

The contour is the set of points (y, z) that fulfill

|2y|^m_upper + |(z - z0)/(0.5 - z0)|^n_upper = 1 for z >= z0; |2y|^m_lower + |(z - z0)/(0.5 + z0)|^n_lower = 1 for z < z0; z0 = lowerHeightFraction - 0.5

The exponents m act on the y term and the exponents n on the z term. Both equal to 2 give half an ellipse; larger values give fuller shapes that approach a rectangle, both equal to 1 give straight lines, and values below 1 give concave, pointed shapes. A rectangle cannot be described exactly, since infinite exponents are not allowed; use rectangle instead.

The following figure shows three examples:

Example mUpper nUpper mLower nLower lowerHeightFraction
(a) pointed top, flat bottom 0.5 2 5 3 0.25
(b) circle 2 2 2 2 0.5
(c) diamond, i.e. a square rotated by 45° 1 1 1 1 0.5
Three superellipse profiles with upper and lower half: pointed top with flat bottom, circle and diamond

Attributes

NameTypeConstraintsUseDefaultDescription
@externalDataDirectoryxsd:stringoptionalDirectory of the external data file
@externalDataNodePathxsd:stringoptionalPath of the node inside the external data file
@externalFileNamexsd:stringoptionalName of the external data file

Child elements

NameTypeConstraintsOccurrenceHow often the element may appear at this place. The schema writes it as minOccurs and maxOccurs on the declaration.DefaultDescription
allThe children below may appear in any order. Each may appear at most once.
mUpperposExcl0DoubleBaseTypeminExclusive[1..1] requiredExponent of the y term of the upper half
nUpperposExcl0DoubleBaseTypeminExclusive[1..1] requiredExponent of the z term of the upper half
mLowerposExcl0DoubleBaseTypeminExclusive[1..1] requiredExponent of the y term of the lower half
nLowerposExcl0DoubleBaseTypeminExclusive[1..1] requiredExponent of the z term of the lower half
lowerHeightFractiondoubleBaseTypeminExclusive, maxExclusive[1..1] requiredHeight of the lower half relative to the total height

Used by

In a dataset · 3 paths

In the schema · 1 declaration

TypeName
standardProfileTypesuperEllipse