Python > Figure Reference > table Traces

Python Figure Reference: table Traces

A plotly.graph_objects.Table trace is a graph object in the figure's data list with any of the named arguments or attributes listed below.

Table view for detailed data viewing. The data are arranged in a grid of rows and columns. Most styling can be specified for columns, rows or individual cells. Table is using a column-major order, ie. the grid is represented as a vector of column vectors.

  • name
    Code: fig.update_traces(name=<VALUE>, selector=dict(type='table'))
    Type: string

    Sets the trace name. The trace name appears as the legend item and on hover.

  • visible
    Code: fig.update_traces(visible=<VALUE>, selector=dict(type='table'))
    Type: enumerated , one of ( True | False | "legendonly" )
    Default: True

    Determines whether or not this trace is visible. If "legendonly", the trace is not drawn, but can appear as a legend item (provided that the legend itself is visible).

  • legend
    Code: fig.update_traces(legend=<VALUE>, selector=dict(type='table'))
    Type: subplotid
    Default: legend

    Sets the reference to a legend to show this trace in. References to these legends are "legend", "legend2", "legend3", etc. Settings for these legends are set in the layout, under `layout.legend`, `layout.legend2`, etc.

  • legendrank
    Code: fig.update_traces(legendrank=<VALUE>, selector=dict(type='table'))
    Type: number
    Default: 1000

    Sets the legend rank for this trace. Items and groups with smaller ranks are presented on top/left side while with "reversed" `legend.traceorder` they are on bottom/right side. The default legendrank is 1000, so that you can use ranks less than 1000 to place certain items before all unranked items, and ranks greater than 1000 to go after all unranked items. When having unranked or equal rank items shapes would be displayed after traces i.e. according to their order in data and layout.

  • legendgrouptitle
    Code: fig.update_traces(legendgrouptitle=dict(...), selector=dict(type='table'))
    Type: dict containing one or more of the keys listed below.
    • font
      Code: fig.update_traces(legendgrouptitle_font=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.

      Sets this legend group's title font.

      • color
        Code: fig.update_traces(legendgrouptitle_font_color=<VALUE>, selector=dict(type='table'))
        Type: color
      • family
        Code: fig.update_traces(legendgrouptitle_font_family=<VALUE>, selector=dict(type='table'))
        Type: string

        HTML font family - the typeface that will be applied by the web browser. The web browser will only be able to apply a font if it is available on the system which it operates. Provide multiple font families, separated by commas, to indicate the preference in which to apply fonts if they aren't available on the system. The Chart Studio Cloud (at https://chart-studio.plotly.com or on-premise) generates images on a server, where only a select number of fonts are installed and supported. These include "Arial", "Balto", "Courier New", "Droid Sans", "Droid Serif", "Droid Sans Mono", "Gravitas One", "Old Standard TT", "Open Sans", "Overpass", "PT Sans Narrow", "Raleway", "Times New Roman".

      • lineposition
        Code: fig.update_traces(legendgrouptitle_font_lineposition=<VALUE>, selector=dict(type='table'))
        Type: flaglist string. Any combination of "under", "over", "through" joined with a "+" OR "none".
        Examples: "under", "over", "under+over", "under+over+through", "none"
        Default: "none"

        Sets the kind of decoration line(s) with text, such as an "under", "over" or "through" as well as combinations e.g. "under+over", etc.

      • shadow
        Code: fig.update_traces(legendgrouptitle_font_shadow=<VALUE>, selector=dict(type='table'))
        Type: string
        Default: "none"

        Sets the shape and color of the shadow behind text. "auto" places minimal shadow and applies contrast text font color. See https://developer.mozilla.org/en-US/docs/Web/CSS/text-shadow for additional options.

      • size
        Code: fig.update_traces(legendgrouptitle_font_size=<VALUE>, selector=dict(type='table'))
        Type: number greater than or equal to 1
      • style
        Code: fig.update_traces(legendgrouptitle_font_style=<VALUE>, selector=dict(type='table'))
        Type: enumerated , one of ( "normal" | "italic" )
        Default: "normal"

        Sets whether a font should be styled with a normal or italic face from its family.

      • textcase
        Code: fig.update_traces(legendgrouptitle_font_textcase=<VALUE>, selector=dict(type='table'))
        Type: enumerated , one of ( "normal" | "word caps" | "upper" | "lower" )
        Default: "normal"

        Sets capitalization of text. It can be used to make text appear in all-uppercase or all-lowercase, or with each word capitalized.

      • variant
        Code: fig.update_traces(legendgrouptitle_font_variant=<VALUE>, selector=dict(type='table'))
        Type: enumerated , one of ( "normal" | "small-caps" | "all-small-caps" | "all-petite-caps" | "petite-caps" | "unicase" )
        Default: "normal"

        Sets the variant of the font.

      • weight
        Code: fig.update_traces(legendgrouptitle_font_weight=<VALUE>, selector=dict(type='table'))
        Type: integer between or equal to 1 and 1000
        Default: normal

        Sets the weight (or boldness) of the font.

    • text
      Code: fig.update_traces(legendgrouptitle_text=<VALUE>, selector=dict(type='table'))
      Type: string
      Default: ""

      Sets the title of the legend group.

  • legendwidth
    Code: fig.update_traces(legendwidth=<VALUE>, selector=dict(type='table'))
    Type: number greater than or equal to 0

    Sets the width (in px or fraction) of the legend for this trace.

  • ids
    Code: fig.update_traces(ids=<VALUE>, selector=dict(type='table'))
    Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.

    Assigns id labels to each datum. These ids for object constancy of data points during animation. Should be an array of strings, not numbers or any other type.

  • columnorder
    Code: fig.update_traces(columnorder=<VALUE>, selector=dict(type='table'))
    Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.

    Specifies the rendered order of the data columns; for example, a value `2` at position `0` means that column index `0` in the data will be rendered as the third column, as columns have an index base of zero.

  • columnwidth
    Code: fig.update_traces(columnwidth=<VALUE>, selector=dict(type='table'))
    Type: number or array of numbers

    The width of columns expressed as a ratio. Columns fill the available width in proportion of their specified column widths.

  • hoverinfo
    Code: fig.update_traces(hoverinfo=<VALUE>, selector=dict(type='table'))
    Type: flaglist string. Any combination of "x", "y", "z", "text", "name" joined with a "+" OR "all" or "none" or "skip".
    Examples: "x", "y", "x+y", "x+y+z", "all"
    Default: "all"

    Determines which trace information appear on hover. If `none` or `skip` are set, no information is displayed upon hovering. But, if `none` is set, click and hover events are still fired.

  • meta
    Code: fig.update_traces(meta=<VALUE>, selector=dict(type='table'))
    Type: number or categorical coordinate string

    Assigns extra meta information associated with this trace that can be used in various text attributes. Attributes such as trace `name`, graph, axis and colorbar `title.text`, annotation `text` `rangeselector`, `updatemenues` and `sliders` `label` text all support `meta`. To access the trace `meta` values in an attribute in the same trace, simply use `%{meta[i]}` where `i` is the index or key of the `meta` item in question. To access trace `meta` in layout attributes, use `%{data[n[.meta[i]}` where `i` is the index or key of the `meta` and `n` is the trace index.

  • customdata
    Code: fig.update_traces(customdata=<VALUE>, selector=dict(type='table'))
    Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.

    Assigns extra data each datum. This may be useful when listening to hover, click and selection events. Note that, "scatter" traces also appends customdata items in the markers DOM elements

  • domain
    Code: fig.update_traces(domain=dict(...), selector=dict(type='table'))
    Type: dict containing one or more of the keys listed below.
    • column
      Code: fig.update_traces(domain_column=<VALUE>, selector=dict(type='table'))
      Type: integer greater than or equal to 0
      Default: 0

      If there is a layout grid, use the domain for this column in the grid for this table trace .

    • row
      Code: fig.update_traces(domain_row=<VALUE>, selector=dict(type='table'))
      Type: integer greater than or equal to 0
      Default: 0

      If there is a layout grid, use the domain for this row in the grid for this table trace .

    • x
      Code: fig.update_traces(domain_x=list(...), selector=dict(type='table'))
      Type: list
      Default: [0, 1]

      Sets the horizontal domain of this table trace (in plot fraction).

    • y
      Code: fig.update_traces(domain_y=list(...), selector=dict(type='table'))
      Type: list
      Default: [0, 1]

      Sets the vertical domain of this table trace (in plot fraction).

  • cells
    Code: fig.update_traces(cells=dict(...), selector=dict(type='table'))
    Type: dict containing one or more of the keys listed below.
    • align
      Code: fig.update_traces(cells_align=<VALUE>, selector=dict(type='table'))
      Type: enumerated or array of enumerateds , one of ( "left" | "center" | "right" )
      Default: "center"

      Sets the horizontal alignment of the `text` within the box. Has an effect only if `text` spans two or more lines (i.e. `text` contains one or more <br> HTML tags) or if an explicit width is set to override the text width.

    • fill
      Code: fig.update_traces(cells_fill=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.
      • color
        Code: fig.update_traces(cells_fill_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
        Default: "white"

        Sets the cell fill color. It accepts either a specific color or an array of colors or a 2D array of colors.

    • font
      Code: fig.update_traces(cells_font=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.
      • color
        Code: fig.update_traces(cells_font_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
      • family
        Code: fig.update_traces(cells_font_family=<VALUE>, selector=dict(type='table'))
        Type: string or array of strings

        HTML font family - the typeface that will be applied by the web browser. The web browser will only be able to apply a font if it is available on the system which it operates. Provide multiple font families, separated by commas, to indicate the preference in which to apply fonts if they aren't available on the system. The Chart Studio Cloud (at https://chart-studio.plotly.com or on-premise) generates images on a server, where only a select number of fonts are installed and supported. These include "Arial", "Balto", "Courier New", "Droid Sans", "Droid Serif", "Droid Sans Mono", "Gravitas One", "Old Standard TT", "Open Sans", "Overpass", "PT Sans Narrow", "Raleway", "Times New Roman".

      • lineposition
        Code: fig.update_traces(cells_font_lineposition=<VALUE>, selector=dict(type='table'))
        Type: flaglist string. Any combination of "under", "over", "through" joined with a "+" OR "none".
        Examples: "under", "over", "under+over", "under+over+through", "none"
        Default: "none"

        Sets the kind of decoration line(s) with text, such as an "under", "over" or "through" as well as combinations e.g. "under+over", etc.

      • shadow
        Code: fig.update_traces(cells_font_shadow=<VALUE>, selector=dict(type='table'))
        Type: string or array of strings
        Default: "none"

        Sets the shape and color of the shadow behind text. "auto" places minimal shadow and applies contrast text font color. See https://developer.mozilla.org/en-US/docs/Web/CSS/text-shadow for additional options.

      • size
        Code: fig.update_traces(cells_font_size=<VALUE>, selector=dict(type='table'))
        Type: number or array of numbers greater than or equal to 1
      • style
        Code: fig.update_traces(cells_font_style=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "italic" )
        Default: "normal"

        Sets whether a font should be styled with a normal or italic face from its family.

      • textcase
        Code: fig.update_traces(cells_font_textcase=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "word caps" | "upper" | "lower" )
        Default: "normal"

        Sets capitalization of text. It can be used to make text appear in all-uppercase or all-lowercase, or with each word capitalized.

      • variant
        Code: fig.update_traces(cells_font_variant=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "small-caps" | "all-small-caps" | "all-petite-caps" | "petite-caps" | "unicase" )
        Default: "normal"

        Sets the variant of the font.

      • weight
        Code: fig.update_traces(cells_font_weight=<VALUE>, selector=dict(type='table'))
        Type: integer or array of integers between or equal to 1 and 1000
        Default: normal

        Sets the weight (or boldness) of the font.

    • format
      Code: fig.update_traces(cells_format=<VALUE>, selector=dict(type='table'))
      Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.
      Default:

      Sets the cell value formatting rule using d3 formatting mini-languages which are very similar to those in Python. For numbers, see: https://github.com/d3/d3-format/tree/v1.4.5#d3-format.

    • height
      Code: fig.update_traces(cells_height=<VALUE>, selector=dict(type='table'))
      Type: number
      Default: 20

      The height of cells.

    • line
      Code: fig.update_traces(cells_line=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.
      • color
        Code: fig.update_traces(cells_line_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
        Default: "grey"
      • width
        Code: fig.update_traces(cells_line_width=<VALUE>, selector=dict(type='table'))
        Type: number or array of numbers
        Default: 1
    • prefix
      Code: fig.update_traces(cells_prefix=<VALUE>, selector=dict(type='table'))
      Type: string or array of strings

      Prefix for cell values.

    • suffix
      Code: fig.update_traces(cells_suffix=<VALUE>, selector=dict(type='table'))
      Type: string or array of strings

      Suffix for cell values.

    • values
      Code: fig.update_traces(cells_values=<VALUE>, selector=dict(type='table'))
      Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.
      Default:

      Cell values. `values[m][n]` represents the value of the `n`th point in column `m`, therefore the `values[m]` vector length for all columns must be the same (longer vectors will be truncated). Each value must be a finite number or a string.

  • header
    Code: fig.update_traces(header=dict(...), selector=dict(type='table'))
    Type: dict containing one or more of the keys listed below.
    • align
      Code: fig.update_traces(header_align=<VALUE>, selector=dict(type='table'))
      Type: enumerated or array of enumerateds , one of ( "left" | "center" | "right" )
      Default: "center"

      Sets the horizontal alignment of the `text` within the box. Has an effect only if `text` spans two or more lines (i.e. `text` contains one or more <br> HTML tags) or if an explicit width is set to override the text width.

    • fill
      Code: fig.update_traces(header_fill=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.
      • color
        Code: fig.update_traces(header_fill_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
        Default: "white"

        Sets the cell fill color. It accepts either a specific color or an array of colors or a 2D array of colors.

    • font
      Code: fig.update_traces(header_font=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.
      • color
        Code: fig.update_traces(header_font_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
      • family
        Code: fig.update_traces(header_font_family=<VALUE>, selector=dict(type='table'))
        Type: string or array of strings

        HTML font family - the typeface that will be applied by the web browser. The web browser will only be able to apply a font if it is available on the system which it operates. Provide multiple font families, separated by commas, to indicate the preference in which to apply fonts if they aren't available on the system. The Chart Studio Cloud (at https://chart-studio.plotly.com or on-premise) generates images on a server, where only a select number of fonts are installed and supported. These include "Arial", "Balto", "Courier New", "Droid Sans", "Droid Serif", "Droid Sans Mono", "Gravitas One", "Old Standard TT", "Open Sans", "Overpass", "PT Sans Narrow", "Raleway", "Times New Roman".

      • lineposition
        Code: fig.update_traces(header_font_lineposition=<VALUE>, selector=dict(type='table'))
        Type: flaglist string. Any combination of "under", "over", "through" joined with a "+" OR "none".
        Examples: "under", "over", "under+over", "under+over+through", "none"
        Default: "none"

        Sets the kind of decoration line(s) with text, such as an "under", "over" or "through" as well as combinations e.g. "under+over", etc.

      • shadow
        Code: fig.update_traces(header_font_shadow=<VALUE>, selector=dict(type='table'))
        Type: string or array of strings
        Default: "none"

        Sets the shape and color of the shadow behind text. "auto" places minimal shadow and applies contrast text font color. See https://developer.mozilla.org/en-US/docs/Web/CSS/text-shadow for additional options.

      • size
        Code: fig.update_traces(header_font_size=<VALUE>, selector=dict(type='table'))
        Type: number or array of numbers greater than or equal to 1
      • style
        Code: fig.update_traces(header_font_style=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "italic" )
        Default: "normal"

        Sets whether a font should be styled with a normal or italic face from its family.

      • textcase
        Code: fig.update_traces(header_font_textcase=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "word caps" | "upper" | "lower" )
        Default: "normal"

        Sets capitalization of text. It can be used to make text appear in all-uppercase or all-lowercase, or with each word capitalized.

      • variant
        Code: fig.update_traces(header_font_variant=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "small-caps" | "all-small-caps" | "all-petite-caps" | "petite-caps" | "unicase" )
        Default: "normal"

        Sets the variant of the font.

      • weight
        Code: fig.update_traces(header_font_weight=<VALUE>, selector=dict(type='table'))
        Type: integer or array of integers between or equal to 1 and 1000
        Default: normal

        Sets the weight (or boldness) of the font.

    • format
      Code: fig.update_traces(header_format=<VALUE>, selector=dict(type='table'))
      Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.
      Default:

      Sets the cell value formatting rule using d3 formatting mini-languages which are very similar to those in Python. For numbers, see: https://github.com/d3/d3-format/tree/v1.4.5#d3-format.

    • height
      Code: fig.update_traces(header_height=<VALUE>, selector=dict(type='table'))
      Type: number
      Default: 28

      The height of cells.

    • line
      Code: fig.update_traces(header_line=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.
      • color
        Code: fig.update_traces(header_line_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
        Default: "grey"
      • width
        Code: fig.update_traces(header_line_width=<VALUE>, selector=dict(type='table'))
        Type: number or array of numbers
        Default: 1
    • prefix
      Code: fig.update_traces(header_prefix=<VALUE>, selector=dict(type='table'))
      Type: string or array of strings

      Prefix for cell values.

    • suffix
      Code: fig.update_traces(header_suffix=<VALUE>, selector=dict(type='table'))
      Type: string or array of strings

      Suffix for cell values.

    • values
      Code: fig.update_traces(header_values=<VALUE>, selector=dict(type='table'))
      Type: list, numpy array, or Pandas series of numbers, strings, or datetimes.
      Default:

      Header cell values. `values[m][n]` represents the value of the `n`th point in column `m`, therefore the `values[m]` vector length for all columns must be the same (longer vectors will be truncated). Each value must be a finite number or a string.

  • hoverlabel
    Code: fig.update_traces(hoverlabel=dict(...), selector=dict(type='table'))
    Type: dict containing one or more of the keys listed below.
    • align
      Code: fig.update_traces(hoverlabel_align=<VALUE>, selector=dict(type='table'))
      Type: enumerated or array of enumerateds , one of ( "left" | "right" | "auto" )
      Default: "auto"

      Sets the horizontal alignment of the text content within hover label box. Has an effect only if the hover label text spans more two or more lines

    • bgcolor
      Code: fig.update_traces(hoverlabel_bgcolor=<VALUE>, selector=dict(type='table'))
      Type: color or array of colors

      Sets the background color of the hover labels for this trace

    • bordercolor
      Code: fig.update_traces(hoverlabel_bordercolor=<VALUE>, selector=dict(type='table'))
      Type: color or array of colors

      Sets the border color of the hover labels for this trace.

    • font
      Code: fig.update_traces(hoverlabel_font=dict(...), selector=dict(type='table'))
      Type: dict containing one or more of the keys listed below.

      Sets the font used in hover labels.

      • color
        Code: fig.update_traces(hoverlabel_font_color=<VALUE>, selector=dict(type='table'))
        Type: color or array of colors
      • family
        Code: fig.update_traces(hoverlabel_font_family=<VALUE>, selector=dict(type='table'))
        Type: string or array of strings

        HTML font family - the typeface that will be applied by the web browser. The web browser will only be able to apply a font if it is available on the system which it operates. Provide multiple font families, separated by commas, to indicate the preference in which to apply fonts if they aren't available on the system. The Chart Studio Cloud (at https://chart-studio.plotly.com or on-premise) generates images on a server, where only a select number of fonts are installed and supported. These include "Arial", "Balto", "Courier New", "Droid Sans", "Droid Serif", "Droid Sans Mono", "Gravitas One", "Old Standard TT", "Open Sans", "Overpass", "PT Sans Narrow", "Raleway", "Times New Roman".

      • lineposition
        Code: fig.update_traces(hoverlabel_font_lineposition=<VALUE>, selector=dict(type='table'))
        Type: flaglist string. Any combination of "under", "over", "through" joined with a "+" OR "none".
        Examples: "under", "over", "under+over", "under+over+through", "none"
        Default: "none"

        Sets the kind of decoration line(s) with text, such as an "under", "over" or "through" as well as combinations e.g. "under+over", etc.

      • shadow
        Code: fig.update_traces(hoverlabel_font_shadow=<VALUE>, selector=dict(type='table'))
        Type: string or array of strings
        Default: "none"

        Sets the shape and color of the shadow behind text. "auto" places minimal shadow and applies contrast text font color. See https://developer.mozilla.org/en-US/docs/Web/CSS/text-shadow for additional options.

      • size
        Code: fig.update_traces(hoverlabel_font_size=<VALUE>, selector=dict(type='table'))
        Type: number or array of numbers greater than or equal to 1
      • style
        Code: fig.update_traces(hoverlabel_font_style=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "italic" )
        Default: "normal"

        Sets whether a font should be styled with a normal or italic face from its family.

      • textcase
        Code: fig.update_traces(hoverlabel_font_textcase=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "word caps" | "upper" | "lower" )
        Default: "normal"

        Sets capitalization of text. It can be used to make text appear in all-uppercase or all-lowercase, or with each word capitalized.

      • variant
        Code: fig.update_traces(hoverlabel_font_variant=<VALUE>, selector=dict(type='table'))
        Type: enumerated or array of enumerateds , one of ( "normal" | "small-caps" | "all-small-caps" | "all-petite-caps" | "petite-caps" | "unicase" )
        Default: "normal"

        Sets the variant of the font.

      • weight
        Code: fig.update_traces(hoverlabel_font_weight=<VALUE>, selector=dict(type='table'))
        Type: integer or array of integers between or equal to 1 and 1000
        Default: normal

        Sets the weight (or boldness) of the font.

    • namelength
      Code: fig.update_traces(hoverlabel_namelength=<VALUE>, selector=dict(type='table'))
      Type: integer or array of integers greater than or equal to -1
      Default: 15

      Sets the default length (in number of characters) of the trace name in the hover labels for all traces. -1 shows the whole name regardless of length. 0-3 shows the first 0-3 characters, and an integer >3 will show the whole name if it is less than that many characters, but if it is longer, will truncate to `namelength - 3` characters and add an ellipsis.

  • uirevision
    Code: fig.update_traces(uirevision=<VALUE>, selector=dict(type='table'))
    Type: number or categorical coordinate string

    Controls persistence of some user-driven changes to the trace: `constraintrange` in `parcoords` traces, as well as some `editable: True` modifications such as `name` and `colorbar.title`. Defaults to `layout.uirevision`. Note that other user-driven trace attribute changes are controlled by `layout` attributes: `trace.visible` is controlled by `layout.legend.uirevision`, `selectedpoints` is controlled by `layout.selectionrevision`, and `colorbar.(x|y)` (accessible with `config: {editable: True}`) is controlled by `layout.editrevision`. Trace changes are tracked by `uid`, which only falls back on trace index if no `uid` is provided. So if your app can add/remove traces before the end of the `data` array, such that the same trace has a different index, you can still preserve user-driven changes if you give each trace a `uid` that stays with it as it moves.