When building a figure, it is *not necessary to populate every attribute* of every object. At render-time, the JavaScript layer will compute default values for each required unspecified attribute, depending upon the ones that are specified, as documented in the [Figure Reference](/python/reference/). An example of this would be `layout.xaxis.range`, which may be specified explicitly, but if not will be computed based on the range of `x` values for every trace linked to that axis. The JavaScript layer will ignore unknown attributes or malformed values, although the `plotly.graph_objects` module provides Python-side validation for attribute values. Note also that if [the `layout.template` key is present (as it is by default)](/python/templates/) then default values will be drawn first from the contents of the template and only if missing from there will the JavaScript layer infer further defaults. The built-in template can be disabled by setting `layout.template="none"`.

The root node of a figure may contain three attributes:

Various figure components configured within the layout of the figure support positioning attributes named `x` or `y`, whose values may be specified in "paper coordinates" (sometimes referred to as "plot fractions" or "normalized coordinates"). Examples include `layout.xaxis.domain` or `layout.legend.x` or `layout.annotation[].x`.

The figure title may be positioned using "container coordinates" which have `(0,0)` and `(1,1)` anchored at the bottom-left and top-right of the figure, respectively, and therefore are independent of the values of layout.margin.

The most commonly-used kind of subplot is a [two-dimensional Cartesian subplot](/python/axes/). Traces compatible with these subplots support `xaxis` and `yaxis` attributes whose values must refer to corresponding objects in the layout portion of the figure. For example, if `xaxis="x"`, and `yaxis="y"` (which is the default) then this trace is drawn on the subplot at the intersection of the axes configured under `layout.xaxis` and `layout.yaxis`, but if `xaxis="x2"` and `yaxis="y3"` then the trace is drawn at the intersection of the axes configured under `layout.xaxis2` and `layout.yaxis3`. Note that attributes such as `layout.xaxis` and `layout.xaxis2` etc do not have to be explicitly defined, in which case default values will be inferred. Multiple traces of different types can be drawn on the same subplot.

* [`carpet`](/python/carpet-plot/): a special trace type for building [carpet plots](/python/carpet-plot/), in that other traces can use as subplots (see below)

* [`splom`](/python/splom/): multi-dimensional scatter plots which implicitly refer to many 2-d cartesian subplots at once.

Beyond 2D cartesian subplots, figures can include [three-dimensional cartesian subplots](/python/3d-charts/), [polar subplots](/python/polar-chart/) and [ternary subplots](/python/ternary-plots/). The following trace types support attributes named `scene`, `polar` or `ternary`, whose values must refer to corresponding objects in the layout portion of the figure i.e. `ternary="ternary2"` etc. Note that attributes such as `layout.scene` and `layout.ternary2` etc do not have to be explicitly defined, in which case default values will be inferred. Multiple traces of a compatible type can be placed on the same subplot.

* [`scatterternary`](/python/ternary-plots/), which can be used to draw individual markers, [curves and filled areas](/python/ternary-contour/)

Figures can include two different types of map subplots: [geo subplots for outline maps](/python/map-configuration/) and [mapbox subplots for tile maps](/python/mapbox-layers/). The following trace types support attributes named `geo` or `mapbox`, whose values must refer to corresponding objects in the layout i.e. `geo="geo2"` etc. Note that attributes such as `layout.geo2` and `layout.mapbox` etc do not have to be explicitly defined, in which case default values will be inferred. Multiple traces of a compatible type can be placed on the same subplot.

* [`choroplethmapbox`](/python/mapbox-county-choropleth/): colored polygons on tile maps

* [`densitymapbox`](/python/mapbox-density-heatmaps/): density heatmaps on tile maps

Certain trace types cannot share subplots, and hence have no attribute to map to a corresponding subplot in the layout. Instead, these traces are their own subplot and support a `domain` attribute for position, which enables the trace to be positioned in paper coordinates (see below). With the exception of `pie` and `funnelarea`, such traces also do not support legends (see below)

* [`table`](/python/table/): [text-based tables](/python/table/)

* [`indicator`](http://indicators/): big numbers, [gauges](/python/gauge-charts/), and [bullet charts](/python/bullet-charts/)

Certain trace types use [traces of type `carpet` as a subplot](/python/carpet-plot/). These support a `carpet` attribute whose value must match the value of the `carpet` attribute of the `carpet` trace they are to be drawn on. Multiple compatible traces can be placed on the same `carpet` trace.

* [`scattercarpet`](/python/carpet-scatter/), which can be used to draw individual markers, curves and filled areas

* [`contourcarpet`](/python/carpet-plot/)

Traces of most types can be optionally associated with a single legend item in the [legend](/python/legend/), which can be shown via the `showlegend` attribute. Traces which are their own subplots (see above) do not support this, with the exception of traces of type `pie` and `funnelarea` for which every distinct color represented in the trace gets a separate legend item. Users may show or hide traces by clicking or double-clicking on their associated legend item. Traces that support legend items also support the `legendgroup` attribute, and all traces with the same legend group are treated the same way during click/double-click interactions.