Re: [Matplotlib-users] Can I change placement of X-Axis?

[John H. <jd...@gm...>]

On Feb 2, 2008 3:06 PM, Eric Firing <ef...@ha...> wrote:
> volcs0 wrote:
> > I saw one post related to arbitrary axis positioning from 2005, but there was
> > no solution.
>
> It is still on the wish list.

Though with a little hacking, you can emulate it by manually drawing
everything yourself -- this is the approach SAGE takes.  Eg,

import numpy as np
from pylab import figure, show
import matplotlib.lines as lines

def make_xaxis(ax, yloc, offset=0.05, **props):
    xmin, xmax = ax.get_xlim()
    locs = [loc for loc in ax.xaxis.get_majorticklocs()
            if loc>=xmin and loc<=xmax]
    tickline, = ax.plot(locs, [yloc]*len(locs),linestyle='',
            marker=lines.TICKDOWN, **props)
    axline, = ax.plot([xmin, xmax], [yloc, yloc], **props)
    tickline.set_clip_on(False)
    axline.set_clip_on(False)
    for loc in locs:
        ax.text(loc, yloc-offset, '%1.1f'%loc,
                horizontalalignment='center',
                verticalalignment='top')

def make_yaxis(ax, xloc=0, offset=0.05, **props):
    ymin, ymax = ax.get_ylim()
    locs = [loc for loc in ax.yaxis.get_majorticklocs()
            if loc>=ymin and loc<=ymax]
    tickline, = ax.plot([xloc]*len(locs), locs, linestyle='',
            marker=lines.TICKLEFT, **props)
    axline, = ax.plot([xloc, xloc], [ymin, ymax], **props)
    tickline.set_clip_on(False)
    axline.set_clip_on(False)

    for loc in locs:
        ax.text(xloc-offset, loc, '%1.1f'%loc,
                verticalalignment='center',
                horizontalalignment='right')


props = dict(color='black', linewidth=2, markeredgewidth=2)
x = np.arange(200.)
y = np.sin(2*np.pi*x/200.) + np.random.rand(200)-0.5
fig = figure(facecolor='white')
ax = fig.add_subplot(111, frame_on=False)
ax.axison = False
ax.plot(x, y, 'd', markersize=8, markerfacecolor='blue')
ax.set_xlim(0, 200)
ax.set_ylim(-1.5, 1.5)
make_xaxis(ax, 0, offset=0.1, **props)
make_yaxis(ax, 0, offset=5, **props)
fig.savefig('manual_axis.png', dpi=100, facecolor='white', edgecolor='white')
show()