Column<T, TInit>

Strongly-typed column. Use get and set to access elements by index.

Extended by

• FloatColumn
• BigIntColumn
• DateTimeColumn
• ObjectColumn
• DataFrameColumn

Type parameters

Type parameter	Value
T	any
TInit	T

Constructors

new Column()

new Column<T, TInit>(dart): Column<T, TInit>

Parameters

Parameter	Type
dart	any

Returns

Column<T, TInit>

Source

src/dataframe.ts:640

Properties

Property	Modifier	Type
_meta	private	undefined | ColumnMetaHelper
dart	public	any
tags	public	any
temp	public	any

Accessors

categories

get categories(): string[]

Returns all unique strings in a sorted order. Applicable to string column only.

Returns

string[]

Source

src/dataframe.ts:1031

---

colors

get colors(): ColumnColorHelper

Returns

ColumnColorHelper

Source

src/dataframe.ts:877

---

dataFrame

get dataFrame(): DataFrame

Parent table

Returns

DataFrame

Source

src/dataframe.ts:832

---

dialogs

get dialogs(): ColumnDialogHelper

Returns

ColumnDialogHelper

Source

src/dataframe.ts:872

---

isCategorical

get isCategorical(): boolean

Is the column categorical (string, boolean)

Returns

boolean

Source

src/dataframe.ts:808

---

isEmpty

get isEmpty(): boolean

Returns whether all values in the columns are empty.

Returns

boolean

Source

src/dataframe.ts:993

---

isNumerical

get isNumerical(): boolean

Is the column numerical (float, int, bigint, qnum)

Returns

boolean

Source

src/dataframe.ts:802

---

isVirtual

get isVirtual(): boolean

Is this column virtual

Returns

boolean

Source

src/dataframe.ts:820

---

layoutColumnId

get layoutColumnId(): string

Layout column ID

set layoutColumnId(s): void

Parameters

Parameter	Type
s	string

Returns

string

Source

src/dataframe.ts:848

---

length

get length(): number

Number of elements

Returns

number

Source

src/dataframe.ts:826

---

markers

get markers(): ColumnMarkerHelper

Returns

ColumnMarkerHelper

Source

src/dataframe.ts:882

---

max

get max(): number

Column's maximum value. The result is cached.

Returns

number

Source

src/dataframe.ts:1060

---

meta

get meta(): ColumnMetaHelper

Returns

ColumnMetaHelper

Source

src/dataframe.ts:646

---

min

get min(): number

Column's minimum value. The result is cached.

Returns

number

Source

src/dataframe.ts:1057

---

name

get name(): string

set name(s): void

Parameters

Parameter	Type
s	string

Returns

string

Source

src/dataframe.ts:857

---

semType

get semType(): string

Semantic type

set semType(s): void

Parameters

Parameter	Type
s	string

Returns

string

Source

src/dataframe.ts:838

---

stats

get stats(): Stats

Basic descriptive statistics. The result is cached.

Returns

Stats

Source

src/dataframe.ts:1070

---

type

get type(): "string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"

Column data type.

Returns

"string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"

Source

src/dataframe.ts:814

---

valueComparer

get valueComparer(): null | Comparer

Value comparison function to be used for sorting. Null means default sorting. Sample: https://public.datagrok.ai/js/samples/data-frame/sorting/custom-comparer

set valueComparer(cmp): void

Parameters

Parameter	Type
cmp	null | Comparer

Returns

null | Comparer

Source

src/dataframe.ts:1053

---

version

get version(): number

Version of the column. Increases each time the column was changed

Returns

number

Source

src/dataframe.ts:867

Methods

aggregate()

aggregate(type): any

Aggregates a column using the [type] function, which corresponds to

• [DG.AGG] for int, bigint, float, qnum columns,
• [DG.STR_AGG] and [DG.STAT_COUNTS] for string columns,
• [DG.STAT_COUNTS], [DG.AGG.MIN], [DG.AGG.MAX], [DG.AGG.AVG] for datetime columns,
• [DG.AGG.TOTAL_COUNT] and [DG.AGG.MISSING_VALUE_COUNT] for virtual columns.

Parameters

Parameter	Type
type	string

Returns

any

Source

src/dataframe.ts:1105

---

applyFormula()

applyFormula(formula, type, treatAsString): Promise<null | Column<any, any>>

Applies the specified formula to a calculated column. Returns a new column object, if applied successfully, and null otherwise.

Parameters

Parameter	Type	Default value
formula	string	undefined
type	null | "string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"	null
treatAsString	boolean	false

Returns

Promise<null | Column<any, any>>

Source

src/dataframe.ts:1081

---

asDoubleList()

asDoubleList(): Float32Array

Returns

Float32Array

• typed array of float values representing the column. Does not guarantee to perform a copy of the underlying data.

Source

src/dataframe.ts:1111

---

clone()

clone(mask?): Column<T, T>

Performs deep cloning, optionally taking mask of the rows to be included. Note that the cloned colum is not added to this column's dataframe.

Parameters

Parameter	Type
mask?	BitSet

Returns

Column<T, T>

Source

src/dataframe.ts:907

---

compact()

compact(): any

Compacts the internal column representation. Currently, it only affects string columns where values were modified.

Returns

any

Source

src/dataframe.ts:1020

---

convertTo()

convertTo(newType, format): Column<any, any>

Creates and returns a new column by converting [column] to the specified [newType].

Parameters

Parameter	Type	Default value
newType	string	undefined
format	null | string	null

Returns

Column<any, any>

Source

src/dataframe.ts:1090

---

fireValuesChanged()

fireValuesChanged(): void

Call this method after setting elements without notifications via set

Returns

void

Source

src/dataframe.ts:977

---

get()

get(row): null | T

Gets i-th value

Parameters

Parameter	Type	Description
row	number	row index

Returns

null | T

• or null if isNone(i)

Source

src/dataframe.ts:945

---

getCategory()

getCategory(categoryIndex): string

Returns i-th category. Applicable to string column only.

Parameters

Parameter	Type
categoryIndex	number

Returns

string

Source

src/dataframe.ts:1036

---

getCategoryOrder()

getCategoryOrder(): string[]

Gets order of categories

Returns

string[]

Source

src/dataframe.ts:1046

---

getNumber()

getNumber(i): number

Returns i-th value as number

Parameters

Parameter	Type	Description
i	number

Returns

number

Source

src/dataframe.ts:960

---

getRawData()

getRawData(): Int32Array | Uint32Array | Float32Array | Float64Array

FOR EXPERT USE ONLY!

Returns the raw buffer containing data. Sample: https://public.datagrok.ai/js/samples/data-frame/performance/access Return type depends on the column type: {Int32Array} for ints, INT_NULL represents null. {Float32Array} or {Float64Array} for floats depending on doublePrecision parameter, FLOAT_NULL represents null. {Float64Array} for qnums, FLOAT_NULL represents null. {Float64Array} for datetime, in microseconds since epoch, FLOAT_NULL represents null. {Int32Array} for strings indexes of categories. {Uint32Array} bit array.

Returns

Int32Array | Uint32Array | Float32Array | Float64Array

Source

src/dataframe.ts:921

---

getSortedOrder()

getSortedOrder(): Int32Array

Returns an array of indexes sorted using [valueComparer].

Returns

Int32Array

Source

src/dataframe.ts:1049

---

getString()

getString(i): string

Returns i-th value as string, taking into account value format defined for the column. An empty string is returned if there is no value.

Parameters

Parameter	Type	Description
i	number

Returns

string

Source

src/dataframe.ts:953

---

getTag()

getTag(tag): string

Returns the value of the specified tag, or null if the tag is not present.

Parameters

Parameter	Type
tag	string

Returns

string

Source

src/dataframe.ts:1005

---

init()

init(valueInitializer): Column<any, any>

Initializes all values in the column to [columnInitializer].

Parameters

Parameter	Type	Description
valueInitializer	null | string | number | boolean | Date | Dayjs | (ind) => any	value, or a function that returns value by index

Returns

Column<any, any>

Source

src/dataframe.ts:891

---

isNone()

isNone(i): boolean

Returns whether i-th value is missing.

Parameters

Parameter	Type	Description
i	number	Row index.

Returns

boolean

Source

src/dataframe.ts:1000

---

matches()

matches(filter): boolean

Checks whether the column passes the specified [filter]. [filter] can be either specific data [type] such as 'int' or 'string', more broadly - 'numerical', or 'categorical', or null for any columns.

Parameters

Parameter	Type
filter	null | "string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe" | "categorical" | "numerical"

Returns

boolean

Source

src/dataframe.ts:1065

---

scale()

scale(idx): number

Linearly maps idx-th value to the [0,1] interval, where 0 represents column minimum, and 1 represents maximum.

Parameters

Parameter	Type
idx	number

Returns

number

Source

src/dataframe.ts:934

---

set()

set(i, value, notify): void

Sets [i]-th value to [x], and optionally notifies the dataframe about this change.

Parameters

Parameter	Type	Default value	Description
i	number	undefined
value	null | TInit	undefined
notify	boolean	true	whether DataFrame's changed event should be fired. Call fireValuesChanged after you are done modifying the column.

Returns

void

Source

src/dataframe.ts:988

---

setCategoryOrder()

setCategoryOrder(order): void

Sets order of categories

Parameters

Parameter	Type
order	string[]

Returns

void

Source

src/dataframe.ts:1041

---

setRawData()

setRawData(rawData, notify): void

Parameters

Parameter	Type	Default value
rawData	Int32Array | Uint32Array | Float32Array | Float64Array	undefined
notify	boolean	true

Returns

void

Source

src/dataframe.ts:938

---

setString()

setString(i, str, notify): boolean

Attempts to set i-th value by converting a provided string to the corresponding strongly-typed value. Returns true if text was successfully parsed and set, otherwise false. Examples: dateColumn.setString('April 1, 2020'); intColumn.setString('42');

Parameters

Parameter	Type	Default value	Description
i	number	undefined
str	string	undefined
notify	boolean	true	whether DataFrame's changed event should be fired

Returns

boolean

Source

src/dataframe.ts:972

---

setTag()

setTag(tag, value): Column<any, any>

Sets a tag to the specified value.

Parameters

Parameter	Type	Description
tag	string	Key.
value	string	Value.

Returns

Column<any, any>

. *

Source

src/dataframe.ts:1013

---

toList()

toList(): any[]

Copies column values to an array. Avoid using this method for performance-critical routines; consider using getRawData

Returns

any[]

Source

src/dataframe.ts:1026

---

toString()

toString(): string

Returns

string

• string representation of this column

Source

src/dataframe.ts:1095

---

values()

values(): Generator<null | T, void, unknown>

An iterator over all values in this column.

Returns

Generator<null | T, void, unknown>

Source

src/dataframe.ts:1073

---

bool()

static bool(name, length): Column<boolean, boolean>

Creates a boolean column with the specified name and length.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0

Returns

Column<boolean, boolean>

Source

src/dataframe.ts:758

---

dataFrame()

static dataFrame(name, length): Column <DataFrame, DataFrame>

Creates a column containing dataframes with the specified name and length.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0

Returns

Column <DataFrame, DataFrame>

Source

src/dataframe.ts:774

---

dateTime()

static dateTime(name, length): Column<any, any>

Creates a datetime column with the specified name and length.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0

Returns

Column<any, any>

Source

src/dataframe.ts:766

---

float()

static float(name, length): Column<number, number>

Creates a floating point column with the specified name and length.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0

Returns

Column<number, number>

Source

src/dataframe.ts:742

---

fromBigInt64Array()

static fromBigInt64Array(name, array): Column<any, any>

Creates BigIntColumn from BigInt64Array / BigUint64Array

Parameters

Parameter	Type
name	string
array	BigInt64Array | BigUint64Array

Returns

Column<any, any>

Source

src/dataframe.ts:695

---

fromBitSet()

static fromBitSet(name, bitset): Column<boolean, boolean>

Creates a Column from the bitset.

Parameters

Parameter	Type	Description
name	string
bitset	BitSet

Returns

Column<boolean, boolean>

Source

src/dataframe.ts:726

---

fromFloat32Array()

static fromFloat32Array(name, array, length): Column<number, number>

[array] will be not be copied and will be used as column's storage

Parameters

Parameter	Type	Default value
name	string	undefined
array	Float32Array	undefined
length	null | number	null

Returns

Column<number, number>

Source

src/dataframe.ts:685

---

fromFloat64Array()

static fromFloat64Array(name, array, length): Column<number, number>

[array] will be not be copied and will be used as column's storage

Parameters

Parameter	Type	Default value
name	string	undefined
array	Float64Array	undefined
length	null | number	null

Returns

Column<number, number>

Source

src/dataframe.ts:690

---

fromIndexes()

static fromIndexes(name, categories, indexes): Column<any, any>

Crates a Column of string type from categories and indexes

Parameters

Parameter	Type	Description
name	string
categories	string[]
indexes	Int32Array

Returns

Column<any, any>

Source

src/dataframe.ts:718

---

fromInt32Array()

static fromInt32Array(name, array, length): Column<number, number>

[array] will be not be copied and will be used as column's storage

Parameters

Parameter	Type	Default value
name	string	undefined
array	Int32Array	undefined
length	null | number	null

Returns

Column<number, number>

Source

src/dataframe.ts:680

---

fromList()

static fromList(type, name, list): Column<any, any>

Creates a Column from the list of values.

Parameters

Parameter	Type	Description
type	"string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"
name	string
list	any[]

Returns

Column<any, any>

Source

src/dataframe.ts:706

---

fromStrings()

static fromStrings(name, list): Column<any, any>

Creates a Column from the list of string values Please note that method performs type promotion if all listed values are numeric

Parameters

Parameter	Type	Description
name	string	Column name
list	string[]	List of column values https://dev.datagrok.ai/script/samples/javascript/data-frame/construction/create-from-columns https://dev.datagrok.ai/script/samples/javascript/data-frame/construction/create-from-arrays

Returns

Column<any, any>

Source

src/dataframe.ts:662

---

fromType()

static fromType(type, name?, length?): Column<any, any>

Creates a Column with explicitly specified type

Parameters

Parameter	Type	Default value	Description
type	"string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"	undefined	column type code COLUMN_TYPE
name?	null | string	undefined	Column name
length?	number	0	Column length (should match row count of the data frame ) DataFrame.create

Returns

Column<any, any>

See

COLUMN_TYPE

Source

src/dataframe.ts:675

---

int()

static int(name, length): Column<number, number>

Creates an integer column with the specified name and length.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0

Returns

Column<number, number>

Source

src/dataframe.ts:734

---

qnum()

static qnum(name, length, values, exact): Column<number, number>

Creates a qualified number column with the specified name and length. Initialized values with [values], if it is specified; strips out the qualifier part if [exact] is true.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0
values	number[]	[]
exact	boolean	true	if true, strips out qualifier from [values].

Returns

Column<number, number>

Source

src/dataframe.ts:787

---

string()

static string(name, length): Column<string, string>

Creates a string column with the specified name and length.

Parameters

Parameter	Type	Default value	Description
name	string	undefined
length	number	0

Returns

Column<string, string>

Source

src/dataframe.ts:750