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Column<T, TInit>

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

Extended by

Type parameters

Type parameterValue
Tany
TInitT

Constructors

new Column()

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

Parameters

ParameterType
dartany

Returns

Column<T, TInit>

Source

src/dataframe.ts:619

Properties

PropertyModifierType
_metaprivateundefined | ColumnMetaHelper
dartpublicany
tagspublicany
temppublicany

Accessors

categories

get categories(): string[]

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

Returns

string[]

Source

src/dataframe.ts:1005


colors

get colors(): ColumnColorHelper

Returns

ColumnColorHelper

Source

src/dataframe.ts:856


dataFrame

get dataFrame(): DataFrame

Parent table

Returns

DataFrame

Source

src/dataframe.ts:811


dialogs

get dialogs(): ColumnDialogHelper

Returns

ColumnDialogHelper

Source

src/dataframe.ts:851


isCategorical

get isCategorical(): boolean

Is the column categorical (string, boolean)

Returns

boolean

Source

src/dataframe.ts:787


isNumerical

get isNumerical(): boolean

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

Returns

boolean

Source

src/dataframe.ts:781


isVirtual

get isVirtual(): boolean

Is this column virtual

Returns

boolean

Source

src/dataframe.ts:799


layoutColumnId

get layoutColumnId(): string

Layout column ID

set layoutColumnId(s): void

Parameters

ParameterType
sstring

Returns

string

Source

src/dataframe.ts:827


length

get length(): number

Number of elements

Returns

number

Source

src/dataframe.ts:805


markers

get markers(): ColumnMarkerHelper

Returns

ColumnMarkerHelper

Source

src/dataframe.ts:861


max

get max(): number

Column's maximum value. The result is cached.

Returns

number

Source

src/dataframe.ts:1034


meta

get meta(): ColumnMetaHelper

Returns

ColumnMetaHelper

Source

src/dataframe.ts:625


min

get min(): number

Column's minimum value. The result is cached.

Returns

number

Source

src/dataframe.ts:1031


name

get name(): string

set name(s): void

Parameters

ParameterType
sstring

Returns

string

Source

src/dataframe.ts:836


semType

get semType(): string

Semantic type

set semType(s): void

Parameters

ParameterType
sstring

Returns

string

Source

src/dataframe.ts:817


stats

get stats(): Stats

Basic descriptive statistics. The result is cached.

Returns

Stats

Source

src/dataframe.ts:1044


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:793


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

ParameterType
cmpnull | Comparer

Returns

null | Comparer

Source

src/dataframe.ts:1027


version

get version(): number

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

Returns

number

Source

src/dataframe.ts:846

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

ParameterType
typestring

Returns

any

Source

src/dataframe.ts:1079


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

ParameterTypeDefault value
formulastringundefined
typenull | "string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"null
treatAsStringbooleanfalse

Returns

Promise<null | Column<any, any>>

Source

src/dataframe.ts:1055


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:1085


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

ParameterType
mask?BitSet

Returns

Column<T, T>

Source

src/dataframe.ts:886


compact()

compact(): any

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

Returns

any

Source

src/dataframe.ts:994


convertTo()

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

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

Parameters

ParameterTypeDefault value
newTypestringundefined
formatnull | stringnull

Returns

Column<any, any>

Source

src/dataframe.ts:1064


fireValuesChanged()

fireValuesChanged(): void

Call this method after setting elements without notifications via set

Returns

void

Source

src/dataframe.ts:956


get()

get(row): null | T

Gets i-th value

Parameters

ParameterTypeDescription
rownumberrow index

Returns

null | T

  • or null if isNone(i)

Source

src/dataframe.ts:924


getCategory()

getCategory(categoryIndex): string

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

Parameters

ParameterType
categoryIndexnumber

Returns

string

Source

src/dataframe.ts:1010


getCategoryOrder()

getCategoryOrder(): string[]

Gets order of categories

Returns

string[]

Source

src/dataframe.ts:1020


getNumber()

getNumber(i): number

Returns i-th value as number

Parameters

ParameterTypeDescription
inumber

Returns

number

Source

src/dataframe.ts:939


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:900


getSortedOrder()

getSortedOrder(): Int32Array

Returns an array of indexes sorted using [valueComparer].

Returns

Int32Array

Source

src/dataframe.ts:1023


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

ParameterTypeDescription
inumber

Returns

string

Source

src/dataframe.ts:932


getTag()

getTag(tag): string

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

Parameters

ParameterType
tagstring

Returns

string

Source

src/dataframe.ts:979


init()

init(valueInitializer): Column<any, any>

Initializes all values in the column to [columnInitializer].

Parameters

ParameterTypeDescription
valueInitializernull | string | number | boolean | Date | Dayjs | (ind) => anyvalue, or a function that returns value by index

Returns

Column<any, any>

Source

src/dataframe.ts:870


isNone()

isNone(i): boolean

Returns whether i-th value is missing.

Parameters

ParameterTypeDescription
inumberRow index.

Returns

boolean

Source

src/dataframe.ts:974


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

ParameterType
filternull | "string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe" | "categorical" | "numerical"

Returns

boolean

Source

src/dataframe.ts:1039


scale()

scale(idx): number

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

Parameters

ParameterType
idxnumber

Returns

number

Source

src/dataframe.ts:913


set()

set(i, value, notify): void

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

Parameters

ParameterTypeDefault valueDescription
inumberundefined
valuenull | TInitundefined
notifybooleantruewhether DataFrame's changed event should be fired. Call fireValuesChanged after you are done modifying the column.

Returns

void

Source

src/dataframe.ts:967


setCategoryOrder()

setCategoryOrder(order): void

Sets order of categories

Parameters

ParameterType
orderstring[]

Returns

void

Source

src/dataframe.ts:1015


setRawData()

setRawData(rawData, notify): void

Parameters

ParameterTypeDefault value
rawDataInt32Array | Uint32Array | Float32Array | Float64Arrayundefined
notifybooleantrue

Returns

void

Source

src/dataframe.ts:917


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

ParameterTypeDefault valueDescription
inumberundefined
strstringundefined
notifybooleantruewhether DataFrame's changed event should be fired

Returns

boolean

Source

src/dataframe.ts:951


setTag()

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

Sets a tag to the specified value.

Parameters

ParameterTypeDescription
tagstringKey.
valuestringValue.

Returns

Column<any, any>

. *

Source

src/dataframe.ts:987


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:1000


toString()

toString(): string

Returns

string

  • string representation of this column

Source

src/dataframe.ts:1069


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:1047


bool()

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

Creates a boolean column with the specified name and length.

Parameters

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0

Returns

Column<boolean, boolean>

Source

src/dataframe.ts:737


dataFrame()

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

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

Parameters

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0

Returns

Column <DataFrame, DataFrame>

Source

src/dataframe.ts:753


dateTime()

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

Creates a datetime column with the specified name and length.

Parameters

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0

Returns

Column<any, any>

Source

src/dataframe.ts:745


float()

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

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

Parameters

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0

Returns

Column<number, number>

Source

src/dataframe.ts:721


fromBigInt64Array()

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

Creates BigIntColumn from BigInt64Array / BigUint64Array

Parameters

ParameterType
namestring
arrayBigInt64Array | BigUint64Array

Returns

Column<any, any>

Source

src/dataframe.ts:674


fromBitSet()

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

Creates a Column from the bitset.

Parameters

ParameterTypeDescription
namestring
bitsetBitSet

Returns

Column<boolean, boolean>

Source

src/dataframe.ts:705


fromFloat32Array()

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

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

Parameters

ParameterTypeDefault value
namestringundefined
arrayFloat32Arrayundefined
lengthnull | numbernull

Returns

Column<number, number>

Source

src/dataframe.ts:664


fromFloat64Array()

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

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

Parameters

ParameterTypeDefault value
namestringundefined
arrayFloat64Arrayundefined
lengthnull | numbernull

Returns

Column<number, number>

Source

src/dataframe.ts:669


fromIndexes()

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

Crates a Column of string type from categories and indexes

Parameters

ParameterTypeDescription
namestring
categoriesstring[]
indexesInt32Array

Returns

Column<any, any>

Source

src/dataframe.ts:697


fromInt32Array()

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

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

Parameters

ParameterTypeDefault value
namestringundefined
arrayInt32Arrayundefined
lengthnull | numbernull

Returns

Column<number, number>

Source

src/dataframe.ts:659


fromList()

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

Creates a Column from the list of values.

Parameters

ParameterTypeDescription
type"string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"
namestring
listany[]

Returns

Column<any, any>

Source

src/dataframe.ts:685


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

ParameterTypeDescription
namestringColumn name
liststring[]

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:641


fromType()

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

Creates a Column with explicitly specified type

Parameters

ParameterTypeDefault valueDescription
type"string" | "bigint" | "object" | "int" | "double" | "bool" | "byte_array" | "datetime" | "qnum" | "dataframe"undefinedcolumn type code COLUMN_TYPE
name?null | stringundefinedColumn name
length?number0

Column length (should match row count of the data frame )

DataFrame.create

Returns

Column<any, any>

See

COLUMN_TYPE

Source

src/dataframe.ts:654


int()

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

Creates an integer column with the specified name and length.

Parameters

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0

Returns

Column<number, number>

Source

src/dataframe.ts:713


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

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0
valuesnumber[][]
exactbooleantrueif true, strips out qualifier from [values].

Returns

Column<number, number>

Source

src/dataframe.ts:766


string()

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

Creates a string column with the specified name and length.

Parameters

ParameterTypeDefault valueDescription
namestringundefined
lengthnumber0

Returns

Column<string, string>

Source

src/dataframe.ts:729