Colorbar axes is a rather special and things need to be set during the
initialization.
Here is a slightly modified version of your script.
While it does not produces error, I'm not sure if the result is correct.
-JJ
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.dates import DateFormatter,DayLocator
from matplotlib import cm
data = np.arange(24.)+700000.
x = np.random.rand(24)
y = np.random.rand(24)
fig = plt.figure()
ax = fig.add_subplot(111)
smap = ax.scatter(x,y,s=10,c=data,edgecolors='none',marker='o',cmap=cm.jet)
cb = fig.colorbar(smap,orientation='horizontal',shrink=0.7,
ticks=DayLocator(interval=5),
format=DateFormatter('%b %d'))
plt.show()
On Thu, Jan 14, 2010 at 3:04 PM, George Nurser <gnur...@googlemail.com> wrote:
> Hi,
> I've got data in terms of day numbers, and wish to plot it as a 2D
> scatter plot, with the color denoting the day.
>
> I'd like the colorbar to be annotated in Apr 7 type format...
>
> I've tried the following code without success.
>
> import numpy as np
> import matplotlib.pyplot as plt
> from matplotlib.dates import DateFormatter,DayLocator
> from matplotlib import cm
>
> data = np.arange(24.)+700000.
> x = np.random.rand(24)
> y = np.random.rand(24)
> fig = plt.figure()
> ax = fig.add_subplot(111)
> smap = ax.scatter(x,y,s=10,c=data,edgecolors='none',marker='o',cmap=cm.jet)
> cb = fig.colorbar(smap,orientation='horizontal',shrink=0.7)
> cax=cb.ax
> cax.xaxis_date()
> cax.xaxis.set_major_locator(DayLocator())
> cax.xaxis.set_major_formatter(DateFormatter('%b %d'))
> plt.show()
>
> Any ideas on how to do this would be appreciated.
>
> George Nurser.
>
> The code fails with the trace
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/backends/backend_wx.pyc
> in _onPaint(self, evt)
> 1154 drawDC = wx.PaintDC(self)
> 1155 if not self._isDrawn:
> -> 1156 self.draw(drawDC=drawDC)
> 1157 else:
> 1158 self.gui_repaint(drawDC=drawDC)
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/backends/backend_wxagg.pyc
> in draw(self, drawDC)
> 57 """
> 58 DEBUG_MSG("draw()", 1, self)
> ---> 59 FigureCanvasAgg.draw(self)
> 60
> 61 self.bitmap =
> _convert_agg_to_wx_bitmap(self.get_renderer(), None)
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/backends/backend_agg.pyc
> in draw(self)
> 386
> 387 self.renderer = self.get_renderer()
> --> 388 self.figure.draw(self.renderer)
> 389
> 390 def get_renderer(self):
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/artist.pyc
> in draw_wrapper(artist, renderer, *kl)
> 53 def draw_wrapper(artist, renderer, *kl):
> 54 before(artist, renderer)
> ---> 55 draw(artist, renderer, *kl)
> 56 after(artist, renderer)
> 57
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/figure.pyc
> in draw(self, renderer)
> 770
> 771 # render the axes
> --> 772 for a in self.axes: a.draw(renderer)
> 773
> 774 # render the figure text
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/artist.pyc
> in draw_wrapper(artist, renderer, *kl)
> 53 def draw_wrapper(artist, renderer, *kl):
> 54 before(artist, renderer)
> ---> 55 draw(artist, renderer, *kl)
> 56 after(artist, renderer)
> 57
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/axes.pyc
> in draw(self, renderer, inframe)
> 1759
> 1760 for zorder, i, a in dsu:
> -> 1761 a.draw(renderer)
> 1762
> 1763 renderer.close_group('axes')
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/artist.pyc
> in draw_wrapper(artist, renderer, *kl)
> 53 def draw_wrapper(artist, renderer, *kl):
> 54 before(artist, renderer)
> ---> 55 draw(artist, renderer, *kl)
> 56 after(artist, renderer)
> 57
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/axis.pyc
> in draw(self, renderer, *args, **kwargs)
> 747 renderer.open_group(__name__)
> 748 interval = self.get_view_interval()
> --> 749 for tick, loc, label in self.iter_ticks():
> 750 if tick is None: continue
> 751 if not mtransforms.interval_contains(interval,
> loc): continue
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/axis.pyc
> in iter_ticks(self)
> 688 Iterate through all of the major and minor ticks.
> 689 """
> --> 690 majorLocs = self.major.locator()
> 691 majorTicks = self.get_major_ticks(len(majorLocs))
> 692 self.major.formatter.set_locs(majorLocs)
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/dates.pyc
> in __call__(self)
> 530 self.rule.set(dtstart=start, until=stop)
> 531 dates = self.rule.between(dmin, dmax, True)
> --> 532 return self.raise_if_exceeds(date2num(dates))
> 533
> 534 def _get_unit(self):
>
> /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/ticker.pyc
> in raise_if_exceeds(self, locs)
> 680 'raise a RuntimeError if Locator attempts to create
> more than MAXTICKS locs'
> 681 if len(locs)>=self.MAXTICKS:
> --> 682 raise RuntimeError('Locator attempting to generate
> %d ticks from %s to %s: exceeds Locator.MAXTICKS'%(len(locs), locs[0],
> locs[-1]))
> 683
> 684 return locs
>
> RuntimeError: Locator attempting to generate 3654 ticks from 730120.0
> to 733773.0: exceeds Locator.MAXTICKS
>
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Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev
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