+++
# -----------------------------------------------------------------------
# Do not edit this file. It is automatically generated by API Documenter.
# -----------------------------------------------------------------------
title = "MutableDataFrame"
keywords = ["grafana","documentation","sdk","@grafana/data"]
type = "docs"
+++
## MutableDataFrame class
Signature
```typescript
export declare class MutableDataFrame extends FunctionalVector implements DataFrame, MutableVector
```
Import
```typescript
import { MutableDataFrame } from '@grafana/data';
```
Constructors
| Constructor | Modifiers | Description |
| --- | --- | --- |
| [constructor(source, creator)](#constructor-sourcecreator) | | Constructs a new instance of the MutableDataFrame
class |
Properties
| Property | Modifiers | Type | Description |
| --- | --- | --- | --- |
| [fields](#fields-property) | | MutableField[]
| |
| [length](#length-property) | | number
| |
| [meta](#meta-property) | | QueryResultMeta
| |
| [name](#name-property) | | string
| |
| [refId](#refid-property) | | string
| |
| [values](#values-property) | | KeyValue<MutableVector>
| |
Methods
| Method | Modifiers | Description |
| --- | --- | --- |
| [add(value, addMissingFields)](#add-method) | | Add all properties of the value as fields on the frame |
| [addField(f, startLength)](#addfield-method) | | |
| [addFieldFor(value, name)](#addfieldfor-method) | | |
| [appendRow(row)](#appendrow-method) | | This will add each value to the corresponding column |
| [get(idx)](#get-method) | | Get an object with a property for each field in the DataFrame |
| [reverse()](#reverse-method) | | Reverse all values |
| [set(index, value, addMissingFields)](#set-method) | | |
| [toJSON()](#tojson-method) | | The simplified JSON values used in JSON.stringify() |
| [validate()](#validate-method) | | |
### constructor(source, creator)
Constructs a new instance of the `MutableDataFrame` class
Signature
```typescript
constructor(source?: DataFrame | DataFrameDTO, creator?: MutableVectorCreator);
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| source | DataFrame | DataFrameDTO
| |
| creator | MutableVectorCreator
| |
### fields property
Signature
```typescript
fields: MutableField[];
```
### length property
Signature
```typescript
get length(): number;
```
### meta property
Signature
```typescript
meta?: QueryResultMeta;
```
### name property
Signature
```typescript
name?: string;
```
### refId property
Signature
```typescript
refId?: string;
```
### values property
Signature
```typescript
values: KeyValue;
```
### add method
Add all properties of the value as fields on the frame
Signature
```typescript
add(value: T, addMissingFields?: boolean): void;
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| value | T
| |
| addMissingFields | boolean
| |
Returns:
`void`
### addField method
Signature
```typescript
addField(f: Field | FieldDTO, startLength?: number): MutableField;
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| f | Field | FieldDTO
| |
| startLength | number
| |
Returns:
`MutableField`
### addFieldFor method
Signature
```typescript
addFieldFor(value: any, name?: string): MutableField;
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| value | any
| |
| name | string
| |
Returns:
`MutableField`
### appendRow method
This will add each value to the corresponding column
Signature
```typescript
appendRow(row: any[]): void;
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| row | any[]
| |
Returns:
`void`
### get method
Get an object with a property for each field in the DataFrame
Signature
```typescript
get(idx: number): T;
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| idx | number
| |
Returns:
`T`
### reverse method
Reverse all values
Signature
```typescript
reverse(): void;
```
Returns:
`void`
### set method
Signature
```typescript
set(index: number, value: T, addMissingFields?: boolean): void;
```
Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| index | number
| |
| value | T
| |
| addMissingFields | boolean
| |
Returns:
`void`
### toJSON method
The simplified JSON values used in JSON.stringify()
Signature
```typescript
toJSON(): DataFrameDTO;
```
Returns:
`DataFrameDTO`
### validate method
Signature
```typescript
validate(): void;
```
Returns:
`void`