integral

integralNode

The area under a curve between two values, shaded. of: takes #bell for a curve in the same environment or an expression to shade directly, and the region is sampled from the curve itself, so it follows an animated expression and a parameter driving either limit. The region closes along the axis: what is shaded is the area between the curve and y = 0, and where the curve dips below the axis the shading follows it down.

Only withxyplane

Writing with it:Reading computed values in prose

#Attributes

ofRequiredImplicit

curve-path

Also written: curve, underThe curve to shade under: #id for a curve in this environment, or an expression shaded directly.Can be written as shorthand: integral:value

fromRequiredAnimatable

parametised-number

Also written: a, startWhere the region starts. May be an expression in the environment's parameters.

toRequiredAnimatable

parametised-number

Also written: b, endWhere it ends. May be an expression in the environment's parameters.

base

curve-path

Also written: down-to, floorWhat the region closes DOWN to: the axis unless this names something else — another curve in the environment (base: #demand) or an expression of its own, and a number is one (base: 6 shades down to that height). The area between two curves is not a special mark, because it is not a special idea: an integral is the region between a function and a floor, and y = 0 is only the floor nothing else was named. The reported value follows, so with a base it is the area BETWEEN.

colourAnimatable

neutralredorangeyellowgreentealbluepurplepinkgreywhiteblack

Also written: colorThe wash and its edges.

Defaultblue

opacityAnimatable

number

How heavy the wash is.

Default0.35

edges

boolean

Draw a line down to the axis at each limit.

Defaulttrue

label

rich-text

Text drawn in the middle of the region — rich text, so $maths$ renders.

hiddenAnimatable

boolean

Declared and framed, but not drawn.

Defaultfalse

lock

boolean

Also written: lockedA reader may not edit it on an editable graph.

Defaultfalse

layerAnimatable

parametised-number

Paint order among the marks: a higher layer is drawn later, on top; equal or omitted, the marks stack in document order (later on top). Written z: before the argand plane took that letter for its coordinate.

#Derived attributes

Computed while the element renders — read one with #id.name in attribute position or {{#id.name}} in prose, never set.

valueDerived

The computed area of the shaded interval — the number the shading is. Cite it with {{#id.value}} and a probability label can never drift from the drawing.

#Allowed in

canvas.graph { }cue { }cue.draw { }cue.trace { }cue.highlight { }cue.spotlight { }

#Examples

integral(of: #bell; from: -1; to: 1; label: $0.68$)

integral(of: x^2; from: 0; to: b; colour: teal)

integral(of: #velocity; a: 0; b: 5; edges: false; opacity: 0.2)