client/util-crossfilter

Utility functions for crossfilter datasets We roughly follow the crossfilter design of dimensions and groups, but we add an extra step to allow transformations on the data.

  1. a datum is turned into a base value using baseValFn;
  2. a base value is transformed into a value (possbily using exceedances, percentiles, category remapping etc.) using valueFn;
  3. a value is grouped using groupFn.
Source:
See:
  • baseValueFn, valueFn, groupFn

Methods

(inner) baseValueFn(facet) → {baseValueCB}

Base value for given facet

Parameters:
Name Type Description
facet Facet
Source:
Returns:

Base value function for this facet

Type
baseValueCB

(inner) groupFn(partition) → {cb}

Create a function that returns the group value for a partition

Parameters:
Name Type Description
partition Partition
Source:
Returns:

Group function for this partition, taking a Data

Type
cb

(inner) reduceFn(facet) → {cb}

/** Returns a function for further reducing the crossfilter group to a single value, depending on sum/count/average settings of the Aggregate class.

Parameters:
Name Type Description
facet Aggregate

The Aggregate class for which to create the reduction function

Source:
Returns:

The required reduction function

Type
cb

(inner) valueFn(facet) → {valueCB}

Create a function that returns the transformed value for this facet

Parameters:
Name Type Description
facet Facet
Source:
Returns:

Value function for this facet

Type
valueCB

Type Definitions

baseValueCB(d) → {Object}

Returns the base value for a datum

Parameters:
Name Type Description
d Object

Raw data record

Source:
Returns:

base value

Type
Object

groupCB(d) → {Object}

Returns the grouped value for a transformed value

Parameters:
Name Type Description
d Object

Transformed value

Source:
Returns:

Group

Type
Object

reduceCB(d) → {number}

Reduce a SubgroupValue to a single number

Parameters:
Name Type Description
d SubgroupValue

SubgroupValue

Source:
Returns:

Reduced value

Type
number

subgroupAverage(d) → {number}

Parameters:
Name Type Description
d SubgroupValue
Source:
Returns:

d.sum/d.count

Type
number

subgroupCount(d) → {number}

Parameters:
Name Type Description
d SubgroupValue
Source:
Returns:

count

Type
number

subgroupSum(d) → {number}

Parameters:
Name Type Description
d SubgroupValue
Source:
Returns:

sum

Type
number

SubgroupValue

Type:
  • Object
Properties:
Name Type Description
count number

The count of the number of elements in this subgroup

sum number

The sum of all elements in this subgroup

Source:

valueCB(d) → {Object}

Returns the transformed value from a base value

Parameters:
Name Type Description
d Object

Base value

Source:
Returns:

Transformed value

Type
Object