GroupByBuilder

Fluid API for building an aggregation query against a DataFrame. Build a query by calling the following methods: key, pivot, count, uniqueCount, missingValueCount, valueCount, min, max, sum, avg, stdev, variance, q1, q2, q3.

When the query is constructed, execute it by calling aggregate, which will produce a DataFrame.

See samples: https://public.datagrok.ai/js/samples/data-frame/aggregation

Example

let avgAgesByRaceAndSex = demographicsTable
  .groupBy(['race', 'sex'])
  .avg('age')
  .aggregate();

Constructors

new GroupByBuilder()

new GroupByBuilder(dart): GroupByBuilder

Parameters

Parameter	Type
dart	any

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:152

Properties

Property	Modifier	Type
dart	private	any

Methods

add()

add(agg, colName?, resultColName?): GroupByBuilder

Adds an aggregation to the query.

Parameters

Parameter	Type	Description
agg	"values" | "max" | "key" | "min" | "sum" | "pivot" | "first" | "count" | "unique" | "nulls" | "med" | "avg" | "stdev" | "variance" | "skew" | "kurt" | "q1" | "q2" | "q3" | "#selected"	Aggregation type.
colName?	null | string	Column name.
resultColName?	null | string	Name of the resulting column. Default value is agg(colName).

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:171

---

aggregate()

aggregate(options?): DataFrame

Performs the aggregation

Parameters

Parameter	Type
options?	object
options.autoName?	boolean

Returns

DataFrame

Source

src/dataframe/stats.ts:158

---

avg()

avg(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates average value for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:274

---

count()

count(resultColName?): GroupByBuilder

Adds an aggregation that counts rows, including these will null values. See also count, valueCount, uniqueCount, missingValueCount Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
resultColName?	string	'count'	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:199

---

first()

first(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that takes first value for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:328

---

getGroups()

getGroups(): Map<string, DataFrame>

Gets groups of DataFrames

Returns

Map<string, DataFrame>

• where keys are stings in format 'columnName=value' and values are DataFrames

Source

src/dataframe/stats.ts:334

---

key()

key(srcColName, resultColName?): GroupByBuilder

Adds a key column to group values on. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:181

---

max()

max(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates maximum value for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:247

---

med()

med(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates median value for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:265

---

min()

min(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates minimum value for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:238

---

missingValueCount()

missingValueCount(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that counts number of missing values in the specified column. See also count, valueCount, uniqueCount, missingValueCount Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:219

---

pivot()

pivot(srcColName, resultColName?): GroupByBuilder

Adds a column to pivot values on. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:190

---

q1()

q1(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates first quartile for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:301

---

q2()

q2(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates second quartile for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:310

---

q3()

q3(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates third quartile for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:319

---

stdev()

stdev(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates standard deviation for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:283

---

sum()

sum(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates sum of the values for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:256

---

toString()

toString(): string

Returns

string

Source

src/dataframe/stats.ts:357

---

uniqueCount()

uniqueCount(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that counts number of unique values in the specified column. See also count, valueCount, missingValueCount Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:209

---

valueCount()

valueCount(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that counts rows, including these will null values. See also count, valueCount, uniqueCount, missingValueCount Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

• this for chaining

Source

src/dataframe/stats.ts:229

---

variance()

variance(srcColName, resultColName?): GroupByBuilder

Adds an aggregation that calculates varians for the specified column. Call aggregate when the query is constructed.

Parameters

Parameter	Type	Default value	Description
srcColName	string	undefined	column name in the source table
resultColName?	null | string	null	column name in the resulting DataFrame

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:292

---

where()

where(pattern): GroupByBuilder

Specifies the filter for the source rows.

Parameters

Parameter	Type
pattern	string | object

Returns

GroupByBuilder

Input

pattern

Source

src/dataframe/stats.ts:343

---

whereRowMask()

whereRowMask(bitset): GroupByBuilder

Parameters

Parameter	Type
bitset	BitSet

Returns

GroupByBuilder

Source

src/dataframe/stats.ts:350