Change length of one (or however many) ticks

Question

I'd like to change the tick length (tick beyond the plot frame) for an arbitrary tick.

I can set the visibility of just one tick (for example the second one) with

ax.xaxis.majorTicks[1].set_visible(False)

So intuitively, I tried the following to no avail:

ax1.xaxis.majorTicks[1].set_length(20)

I looked through the axes object and tried some other things, for example setting one to the color blue with the following code, again to no avail:

ax1.xaxis.majorTicks[1]._color = 'blue'

Is this possible?

Answer 1

The tick is a marker of a Line2D. The line is accessed as tick1line (or tick2line in case of the opposite axis).

ax1.xaxis.get_major_ticks()[3].tick1line.set_color("red")
ax1.xaxis.get_major_ticks()[3].tick1line.set_markersize(8)
ax1.xaxis.get_major_ticks()[3].tick1line.set_markeredgewidth(3)