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Class pv.Scale.root

Extends pv.Scale.quantitative.
Represents a root scale; a function that performs a power transformation. Most commonly, a root scale represents a 1-dimensional root transformation from a numeric domain of input data [d0, d1] to a numeric range of pixels [r0, r1].

Note that the scale is itself a function, and thus can be used as a property directly, assuming that the data associated with a mark is a number. While this is convenient for single-use scales, frequently it is desirable to define scales globally:

var y = pv.Scale.root(0, 100).range(0, 640);
The y scale can now be equivalently referenced within a property:
    .height(function(d) y(d))
Alternatively, if the data are not simple numbers, the appropriate value can be passed to the y scale (e.g., The #by method similarly allows the data to be mapped to a numeric value before performing the root transformation.
Defined in: RootScale.js.

Class Summary
Constructor Attributes Constructor Name and Description
Returns a root scale for the specified domain.
Method Summary
Method Attributes Method Name and Description
Sets or gets the exponent; defaults to 2.
Methods borrowed from class pv.Scale.quantitative:
by, domain, invert, nice, range, tickFormat, ticks
Class Detail
Returns a root scale for the specified domain. The arguments to this constructor are optional, and equivalent to calling #domain. The default domain and range are [0,1].
{number...} domain...
optional domain values.
Method Detail
{pv.Scale.root} power(v)
Sets or gets the exponent; defaults to 2.
{number} v Optional
the new exponent.
{pv.Scale.root} this, or the current base.

Documentation generated by JsDoc Toolkit 2.3.2 on Sun May 30 2010 18:10:25 GMT-0700 (PDT)