Set several scatter traces (on the same subplot) to the same stackgroup in order to add their y values (or their x values if `orientation` is *h*). If blank or omitted this trace will not be stacked. Stacking also turns `fill` on by default, using *tonexty* (*tonextx*) if `orientation` is *h* (*v*) and sets the default `mode` to *lines* irrespective of point count. You can only stack on a numeric (linear or log) axis. Traces in a `stackgroup` will only fill to (or be filled to) other traces in the same group. With multiple `stackgroup`s or some traces stacked and some not, if fill-linked traces are not already consecutive, the later ones will be pushed down in the drawing order.

Template string used for rendering the information text that appear on points. Note that this will override `textinfo`. Variables are inserted using %{variable}, for example "y: %{y}". Numbers are formatted using d3-format's syntax %{variable:d3-format}, for example "Price: %{y:$.2f}". https://github.com/d3/d3-format/tree/v1.4.5#d3-format for details on the formatting syntax. Dates are formatted using d3-time-format's syntax %{variable|d3-time-format}, for example "Day: %{2019-01-01|%A}". https://github.com/d3/d3-time-format/tree/v2.2.3#locale_format for details on the date formatting syntax. Every attributes that can be specified per-point (the ones that are `arrayOk: true`) are available.

The scatter trace type encompasses line charts, scatter charts, text charts, and bubble charts. The data visualized as scatter point or lines is set in `x` and `y`. Text (appearing either on the chart or on hover only) is via `text`. Bubble charts are achieved by setting `marker.size` and/or `marker.color` to numerical arrays.

Sets text elements associated with each (x,y,z) triplet. If a single string, the same string appears over all the data points. If an array of string, the items are mapped in order to the this trace's (x,y,z) coordinates. To be seen, trace `hoverinfo` must contain a *text* flag.

Sets the marker opacity. Note that the marker opacity for scatter3d traces must be a scalar value for performance reasons. To set a blending opacity value (i.e. which is not transparent), set *marker.color* to an rgba color and use its alpha channel.