tickmode

Sets the tick mode for this axis. If "auto", the number of ticks is set via nticks. If "linear", the placement of the ticks is determined by a starting position tick0 and a tick step dtick ("linear" is the default value if tick0 and dtick are provided). If "array", the placement of the ticks is set via tickvals and the tick text is ticktext. ("array" is the default value if tickvals is provided).