com.github.gwtd3.api

Class Scales

java.lang.Object

com.google.gwt.core.client.JavaScriptObject

com.github.gwtd3.api.Scales

public class Scales
extends com.google.gwt.core.client.JavaScriptObject

Factory for Scales.

Scales are functions that map from an input domain to an output range. There is 3 kind of scales:

• Quantitative Scales - for continuous input domains, such as numbers.
• Ordinal Scales - for discrete input domains, such as names or categories.
• Time Scales - for time domains. See D3.time().

Quantitative scales

Quantitative scales have a continuous domain, such as the set of real numbers, or dates. There are also ordinal scales, which have a discrete domain, such as a set of names or categories. Scales are an optional feature in D3; you don't have to use them, if you prefer to do the math yourself. However, using scales can greatly simplify the code needed to map a dimension of data to a visual representation. A scale object, such as that returned by d3.scale.linear, is both an object and a function. That is: you can call the scale like any other function, and the scale has additional methods that change its behavior. Like other classes in D3, scales follow the method chaining pattern where setter methods return the scale itself, allowing multiple setters to be invoked in a concise statement.

Author:

Anthony Schiochet

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Scales()

Method Summary

Methods

Modifier and Type	Method and Description
OrdinalScale	category10() Constructs a new ordinal scale with a range of ten categorical colors: #1f77b4 #ff7f0e #2ca02c #d62728 #9467bd #8c564b #e377c2 #7f7f7f #bcbd22 #17becf.
OrdinalScale	category20() Constructs a new ordinal scale with a range of twenty categorical colors: #1f77b4 #aec7e8 #ff7f0e #ffbb78 #2ca02c #98df8a #d62728 #ff9896 #9467bd #c5b0d5 #8c564b #c49c94 #e377c2 #f7b6d2 #7f7f7f #c7c7c7 #bcbd22 #dbdb8d #17becf #9edae5.
OrdinalScale	category20b() Constructs a new ordinal scale with a range of twenty categorical colors: #393b79 #5254a3 #6b6ecf #9c9ede #637939 #8ca252 #b5cf6b #cedb9c #8c6d31 #bd9e39 #e7ba52 #e7cb94 #843c39 #ad494a #d6616b #e7969c #7b4173 #a55194 #ce6dbd #de9ed6.
OrdinalScale	category20c() Constructs a new ordinal scale with a range of twenty categorical colors: #3182bd #6baed6 #9ecae1 #c6dbef #e6550d #fd8d3c #fdae6b #fdd0a2 #31a354 #74c476 #a1d99b #c7e9c0 #756bb1 #9e9ac8 #bcbddc #dadaeb #636363 #969696 #bdbdbd #d9d9d9.
static Scales	get()
IdentityScale	identity() Constructs a new identity scale with the default domain [0,1] and the default range [0,1].
LinearScale	linear() Constructs a new linear scale with the default domain [0,1] and the default range [0,1].
LogScale	log() Constructs a new log scale with the default domain [1,10], the default range [0,1], and the base 10.
OrdinalScale	ordinal() Constructs a new ordinal scale with an empty domain and an empty range.
PowScale	pow() Constructs a new power scale with the default domain [0,1], the default range [0,1], and the default exponent 1.
QuantileScale	quantile() Constructs a new quantile scale with an empty domain and an empty range.
QuantizeScale	quantize() Constructs a new quantize scale with the default domain [0,1] and the default range [0,1].
PowScale	sqrt() Constructs a new power scale with the default domain [0,1], the default range [0,1], and the exponent .5.
ThresholdScale	threshold() Constructs a new threshold scale with the default domain [.5] and the default range [0,1].

Methods inherited from class com.google.gwt.core.client.JavaScriptObject

cast, createArray, createArray, createFunction, createObject, equals, hashCode, toSource, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Scales

protected Scales()

Method Detail

linear

public final LinearScale linear()

Constructs a new linear scale with the default domain [0,1] and the default range [0,1]. Thus, the default linear scale is equivalent to the identity function for numbers; for example linear(0.5) returns 0.5.

Returns:

a new default linear scale

identity

public final IdentityScale identity()

Constructs a new identity scale with the default domain [0,1] and the default range [0,1]. An identity scale is always equivalent to the identity function.

Returns:

a new identity scale

log

public final LogScale log()

Constructs a new log scale with the default domain [1,10], the default range [0,1], and the base 10.

Returns:

a new default log scale

pow

public final PowScale pow()

Constructs a new power scale with the default domain [0,1], the default range [0,1], and the default exponent 1.

Thus, the default power scale is equivalent to the identity function for numbers; for example pow(0.5) returns 0.5.

Returns:

a new default pow scale

sqrt

public final PowScale sqrt()

Constructs a new power scale with the default domain [0,1], the default range [0,1], and the exponent .5. This method is shorthand for:

 D3.scale.pow().exponent(.5);
 
 

The returned scale is a function that takes a single argument x representing a value in the input domain; the return value is the corresponding value in the output range. Thus, the returned scale is equivalent to the Math.sqrt(double) function for numbers; for example sqrt(0.25) returns 0.5.

Returns:

a new default pow scale with an exponent of 0.5.

quantize

public final QuantizeScale quantize()

Constructs a new quantize scale with the default domain [0,1] and the default range [0,1].

Thus, the default quantize scale is equivalent to the round function for numbers; for example quantize(0.49) returns 0, and quantize(0.51) returns 1.

Returns:

the new scale

quantile

public final QuantileScale quantile()

Constructs a new quantile scale with an empty domain and an empty range.

The quantile scale is invalid until both a domain and range are specified.

Returns:

the new empty quantile scale

ordinal

public final OrdinalScale ordinal()

Constructs a new ordinal scale with an empty domain and an empty range.

The ordinal scale is invalid (always returning undefined) until an output range is specified.

Returns:

the new ordinal scale

threshold

public final ThresholdScale threshold()

Constructs a new threshold scale with the default domain [.5] and the default range [0,1].

Thus, the default threshold scale is equivalent to the round function for numbers; for example threshold(0.49) returns 0, and threshold(0.51) returns 1.

Returns:

the new threshold scale

category10

public final OrdinalScale category10()

Constructs a new ordinal scale with a range of ten categorical colors: #1f77b4 #ff7f0e #2ca02c #d62728 #9467bd #8c564b #e377c2 #7f7f7f #bcbd22 #17becf.

Returns:

the color palette as a OrdinalScale

category20

public final OrdinalScale category20()

Constructs a new ordinal scale with a range of twenty categorical colors: #1f77b4 #aec7e8 #ff7f0e #ffbb78 #2ca02c #98df8a #d62728 #ff9896 #9467bd #c5b0d5 #8c564b #c49c94 #e377c2 #f7b6d2 #7f7f7f #c7c7c7 #bcbd22 #dbdb8d #17becf #9edae5.

Returns:

the color palette as a OrdinalScale

category20b

public final OrdinalScale category20b()

Constructs a new ordinal scale with a range of twenty categorical colors: #393b79 #5254a3 #6b6ecf #9c9ede #637939 #8ca252 #b5cf6b #cedb9c #8c6d31 #bd9e39 #e7ba52 #e7cb94 #843c39 #ad494a #d6616b #e7969c #7b4173 #a55194 #ce6dbd #de9ed6.

Returns:

the color palette as a OrdinalScale

category20c

public final OrdinalScale category20c()

Constructs a new ordinal scale with a range of twenty categorical colors: #3182bd #6baed6 #9ecae1 #c6dbef #e6550d #fd8d3c #fdae6b #fdd0a2 #31a354 #74c476 #a1d99b #c7e9c0 #756bb1 #9e9ac8 #bcbddc #dadaeb #636363 #969696 #bdbdbd #d9d9d9.

Returns:

the color palette as a OrdinalScale

get

public static final Scales get()

Returns: