Is the first row the top or the bottom? Note that columns are always enumerated from left to right.

The number of rows in the grid. If you provide a 2D `subplots` array or a `yaxes` array, its length is used as the default. But it's also possible to have a different length, if you want to leave a row at the end for non-cartesian subplots.

Used for freeform grids, where some axes may be shared across subplots but others are not. Each entry should be a cartesian subplot id, like *xy* or *x3y2*, or ** to leave that cell empty. You may reuse x axes within the same column, and y axes within the same row. Non-cartesian subplots and traces that support `domain` can place themselves in this grid separately using the `gridcell` attribute.

Used with `yaxes` when the x and y axes are shared across columns and rows. Each entry should be an x axis id like *x*, *x2*, etc., or ** to not put an x axis in that column. Entries other than ** must be unique. Ignored if `subplots` is present. If missing but `yaxes` is present, will generate consecutive IDs.

Horizontal space between grid cells, expressed as a fraction of the total width available to one cell. Defaults to 0.1 for coupled-axes grids and 0.2 for independent grids.

Sets where the x axis labels and titles go. *bottom* means the very bottom of the grid. *bottom plot* is the lowest plot that each x axis is used in. *top* and *top plot* are similar.

Used with `yaxes` when the x and y axes are shared across columns and rows. Each entry should be an y axis id like *y*, *y2*, etc., or ** to not put a y axis in that row. Entries other than ** must be unique. Ignored if `subplots` is present. If missing but `xaxes` is present, will generate consecutive IDs.

Vertical space between grid cells, expressed as a fraction of the total height available to one cell. Defaults to 0.1 for coupled-axes grids and 0.3 for independent grids.

Sets where the y axis labels and titles go. *left* means the very left edge of the grid. *left plot* is the leftmost plot that each y axis is used in. *right* and *right plot* are similar.