Arrowheads

• With the default Arrowheads[Automatic] a single arrowhead is placed at the head of each arrow.

• Arrowheads[s] specifies that arrowheads should have a length that is a fraction s of the total width of the graphic. The default is 0.04.  »

• The symbolic values Tiny, Small, Medium and Large can be used for s. With these values the size of the arrowhead is independent of the total width of the graphic.  »

• Arrowheads[{spec₁, spec₂, ...}] specifies that arrows should include several arrowhead elements.

• Each arrowhead element can be specified as follows:

• The position pos runs from 0 to 1 from the tail to the head of the arrow.

• Arrowheads[{s₀, s₁, ..., s_n}] specifies arrowheads with scaled sizes s_i at positions i/n.  »

• Arrowheads[{-s, s}] gives double-headed arrows.  »

• The graphic g is placed so that the origin of its coordinates lies at position pos along each arrow.

• The graphic g is oriented so that its positive x axis is aligned with the direction of the shaft at position pos.

• The graphic g is scaled so that one unit of its coordinates corresponds to a fraction s of the width of the whole graphic in which the arrow is being drawn.

• The graphic g is always assumed to have AspectRatio->Automatic.

• With the specification {s, pos, {g, }}, the shaft of the arrow is foreshortened by in the coordinate system of g. This can prevent a thick shaft from "poking through" arrowheads at the head or tail of the arrow.  »