marker: An element to create a marker arrowheads, tails, ...
In mslegrand/svgR: svgR is an R DSL to generate svg markup

Description Available Attributes (Named Parameters) Available Content Elements (Unnamed Parameters)

The marker element defines the graphics that is to be used for drawing arrowheads or polymarkers on a given <path>, <line>, <polyline> or <polygon> element.

Complementary Attributes: refXY
Core Attributes: id, xml.base, xml.lang, xml.space
Presentation Attributes: clip, clip.path, color.interpolation, color.rendering, cursor, enable.background, filter, mask, opacity, overflow
Unclassified: class, externalResourcesRequired, markerHeight, markerUnits, markerWidth, orient, preserveAspectRatio, refX, refY, style, viewBox

Animation Elements: animate, animateColor, animateMotion, animateTransform, set
Descriptive Elements: desc, metadata, title
Gradient Elements: linearGradient, radialGradient
Graphics Referencing Elements: image, use
Non-structural Container Elements: a, marker, mask, pattern, switch
Shape Elements: circle, ellipse, line, path, polygon, polyline, rect
Structural Container Elements: defs, g, svg, symbol
Text Content Elements: text
Uncategorized Elements: altGlyphDef, clipPath, color.profile, cursor, filter, font, font.face, foreignObject, script, style, view