Re: [Matplotlib-users] quickly return colorbar ticks?

[Benjamin R. <ben...@ou...>]

On Wed, Jul 3, 2013 at 3:13 AM, ChaoYue <cha...@gm...> wrote:

> Thanks Ben. I tried but still confused.
>
> In [8]: fig,ax = plt.subplots()
>
> In [9]: ax.plot(range(100))
> Out[9]: [<matplotlib.lines.Line2D at 0x4cadb50>]
>
> In [10]: ax.get_xticks()
> Out[10]: array([   0.,   20.,   40.,   60.,   80.,  100.])
>
> In [11]: ax.get_yticks()
> Out[11]: array([   0.,   20.,   40.,   60.,   80.,  100.])
>
> In [12]: draw()
>
> In [13]: cs = ax.imshow(np.arange(100).reshape(10,10))
>
> In [14]: draw()
>
> In [15]: cbar = plt.colorbar(cs,ticks=np.arange(0,100,10))
>
> In [16]: cbar.ax.get_yticks()
> Out[16]:
> array([ 0.        ,  0.1010101 ,  0.2020202 ,  0.3030303 ,  0.4040404 ,
>         0.50505051,  0.60606061,  0.70707071,  0.80808081,  0.90909091])
>
> there are many methods avaialbe for cbar.ax.yaxis object:
> In [19]: cbar.ax.yaxis.get*tick*?
> cbar.ax.yaxis.get_major_ticks
> cbar.ax.yaxis.get_majorticklabels
> cbar.ax.yaxis.get_majorticklines
> cbar.ax.yaxis.get_majorticklocs
> cbar.ax.yaxis.get_minor_ticks
> cbar.ax.yaxis.get_minorticklabels
> cbar.ax.yaxis.get_minorticklines
> cbar.ax.yaxis.get_minorticklocs
> cbar.ax.yaxis.get_ticklabel_extents
> cbar.ax.yaxis.get_ticklabels
> cbar.ax.yaxis.get_ticklines
> cbar.ax.yaxis.get_ticklocs
> cbar.ax.yaxis.get_ticks_position
>
> I tried
> In [20]: cbar.ax.yaxis.get_majorticklocs()
> Out[20]:
> array([ 0.        ,  0.1010101 ,  0.2020202 ,  0.3030303 ,  0.4040404 ,
>         0.50505051,  0.60606061,  0.70707071,  0.80808081,  0.90909091])
>
> But it doesn't give the tick locs as the normal axes?
>
> could you explain a bit further?
>
> thanks et cheers,
>
> Chao
>
>
Remember, there is a difference between a tick location, and a tick label.
A colormap works from 0 to 1, so that is its data coordinates.  We merely
label the ticks with the appropriate values.  Try
cbar.ax.yaxis.get_ticklabels().

Cheers!
Ben Root