Tick locating and formatting
============================
 
This module contains classes to support completely configurable tick
locating and formatting.  Although the locators know nothing about
major or minor ticks, they are used by the Axis class to support major
and minor tick locating and formatting.  Generic tick locators and
formatters are provided, as well as domain specific custom ones..
 
 
Tick locating
-------------
 
The Locator class is the base class for all tick locators.  The
locators handle autoscaling of the view limits based on the data
limits, and the choosing of tick locations.  A useful semi-automatic
tick locator is MultipleLocator.  You initialize this with a base, eg
10, and it picks axis limits and ticks that are multiples of your
base.
 
The Locator subclasses defined here are
 
  * NullLocator     - No ticks
 
  * FixedLocator    - Tick locations are fixed
 
  * IndexLocator    - locator for index plots (eg where x = range(len(y))
 
  * LinearLocator   - evenly spaced ticks from min to max
 
  * LogLocator      - logarithmically ticks from min to max
 
  * MultipleLocator - ticks and range are a multiple of base;
                      either integer or float
 
  * OldAutoLocator  - choose a MultipleLocator and dyamically reassign
                      it for intelligent ticking during navigation
 
  * MaxNLocator     - finds up to a max number of ticks at nice
                      locations
 
  * AutoLocator     - MaxNLocator with simple defaults. This is the
                      default tick locator for most plotting.
 
There are a number of locators specialized for date locations - see
the dates module
 
You can define your own locator by deriving from Locator.  You must
override the __call__ method, which returns a sequence of locations,
and you will probably want to override the autoscale method to set the
view limits from the data limits.
 
If you want to override the default locator, use one of the above or a
custom locator and pass it to the x or y axis instance.  The relevant
methods are::
 
  ax.xaxis.set_major_locator( xmajorLocator )
  ax.xaxis.set_minor_locator( xminorLocator )
  ax.yaxis.set_major_locator( ymajorLocator )
  ax.yaxis.set_minor_locator( yminorLocator )
 
The default minor locator is the NullLocator, eg no minor ticks on by
default.
 
Tick formatting
---------------
 
Tick formatting is controlled by classes derived from Formatter.  The
formatter operates on a single tick value and returns a string to the
axis.
 
  * NullFormatter      - no labels on the ticks
 
  * FixedFormatter     - set the strings manually for the labels
 
  * FuncFormatter      - user defined function sets the labels
 
  * FormatStrFormatter - use a sprintf format string
 
  * ScalarFormatter    - default formatter for scalars; autopick the fmt string
 
  * LogFormatter       - formatter for log axes
 
 
You can derive your own formatter from the Formatter base class by
simply overriding the __call__ method.  The formatter class has access
to the axis view and data limits.
 
To control the major and minor tick label formats, use one of the
following methods::
 
  ax.xaxis.set_major_formatter( xmajorFormatter )
  ax.xaxis.set_minor_formatter( xminorFormatter )
  ax.yaxis.set_major_formatter( ymajorFormatter )
  ax.yaxis.set_minor_formatter( yminorFormatter )
 
See examples/major_minor_demo1.py for an example of setting major an
minor ticks.  See the matplotlib.dates module for more information and
examples of using date locators and formatters.

Modules
		matplotlib.cbook math matplotlib.transforms numpy

Classes
		TickHelper Formatter FixedFormatter FormatStrFormatter FuncFormatter LogFormatter LogFormatterExponent LogFormatterMathtext NullFormatter ScalarFormatter Locator FixedLocator IndexLocator LinearLocator LogLocator MaxNLocator AutoLocator MultipleLocator NullLocator   class AutoLocator(MaxNLocator)       Method resolution order: AutoLocator MaxNLocator Locator TickHelper Methods defined here: __init__(self) Methods inherited from MaxNLocator: __call__(self) autoscale(self) bin_boundaries(self, vmin, vmax) Methods inherited from Locator: pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class FixedFormatter(Formatter)     Return fixed strings for tick labels     Method resolution order: FixedFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos __init__(self, seq) seq is a sequence of strings.  For positions i<len(seq) return seq[i] regardless of x.  Otherwise return '' get_offset(self) set_offset_string(self, ofs) Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method format_data(self, value) format_data_short(self, value) return a short string version set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class FixedLocator(Locator)     Tick locations are fixed.  If nbins is not None, the array of possible positions will be subsampled to keep the number of ticks <= nbins +1.     Method resolution order: FixedLocator Locator TickHelper Methods defined here: __call__(self) Return the locations of the ticks __init__(self, locs, nbins=None) Methods inherited from Locator: autoscale(self) autoscale the view limits pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class FormatStrFormatter(Formatter)     Use a format string to format the tick     Method resolution order: FormatStrFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos __init__(self, fmt) Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method format_data(self, value) format_data_short(self, value) return a short string version get_offset(self) set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class Formatter(TickHelper)     Convert the tick location to a string     Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos; pos=None indicated unspecified fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method format_data(self, value) format_data_short(self, value) return a short string version get_offset(self) set_locs(self, locs) Data and other attributes defined here: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class FuncFormatter(Formatter)     User defined function for formatting     Method resolution order: FuncFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos __init__(self, func) Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method format_data(self, value) format_data_short(self, value) return a short string version get_offset(self) set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class IndexLocator(Locator)     Place a tick on every multiple of some base number of points plotted, eg on every 5th point.  It is assumed that you are doing index plotting; ie the axis is 0, len(data).  This is mainly useful for x ticks.     Method resolution order: IndexLocator Locator TickHelper Methods defined here: __call__(self) Return the locations of the ticks __init__(self, base, offset) place ticks on the i-th data points where (i-offset)%base==0 Methods inherited from Locator: autoscale(self) autoscale the view limits pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class LinearLocator(Locator)     Determine the tick locations   The first time this function is called it will try to set the number of ticks to make a nice tick partitioning.  Thereafter the number of ticks will be fixed so that interactive navigation will be nice     Method resolution order: LinearLocator Locator TickHelper Methods defined here: __call__(self) Return the locations of the ticks __init__(self, numticks=None, presets=None) Use presets to set locs based on lom.  A dict mapping vmin, vmax->locs autoscale(self) Try to choose the view limits intelligently Methods inherited from Locator: pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class Locator(TickHelper)     Determine the tick locations;   Note, you should not use the same locator between different Axis because the locator stores references to the Axis data and view limits     Methods defined here: __call__(self) Return the locations of the ticks autoscale(self) autoscale the view limits pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class LogFormatter(Formatter)     Format values for log axis;   if attribute decadeOnly is True, only the decades will be labelled.     Method resolution order: LogFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos __init__(self, base=10.0, labelOnlyBase=True) base is used to locate the decade tick, which will be the only one to be labeled if labelOnlyBase is False base(self, base) change the base for labeling - warning: should always match the base used for LogLocator format_data(self, value) format_data_short(self, value) return a short formatted string representation of a number is_decade(self, x) label_minor(self, labelOnlyBase) switch on/off minor ticks labeling nearest_long(self, x) pprint_val(self, x, d) Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method get_offset(self) set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class LogFormatterExponent(LogFormatter)     Format values for log axis; using exponent = log_base(value)     Method resolution order: LogFormatterExponent LogFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos Methods inherited from LogFormatter: __init__(self, base=10.0, labelOnlyBase=True) base is used to locate the decade tick, which will be the only one to be labeled if labelOnlyBase is False base(self, base) change the base for labeling - warning: should always match the base used for LogLocator format_data(self, value) format_data_short(self, value) return a short formatted string representation of a number is_decade(self, x) label_minor(self, labelOnlyBase) switch on/off minor ticks labeling nearest_long(self, x) pprint_val(self, x, d) Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method get_offset(self) set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class LogFormatterMathtext(LogFormatter)     Format values for log axis; using exponent = log_base(value)     Method resolution order: LogFormatterMathtext LogFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos Methods inherited from LogFormatter: __init__(self, base=10.0, labelOnlyBase=True) base is used to locate the decade tick, which will be the only one to be labeled if labelOnlyBase is False base(self, base) change the base for labeling - warning: should always match the base used for LogLocator format_data(self, value) format_data_short(self, value) return a short formatted string representation of a number is_decade(self, x) label_minor(self, labelOnlyBase) switch on/off minor ticks labeling nearest_long(self, x) pprint_val(self, x, d) Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method get_offset(self) set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class LogLocator(Locator)     Determine the tick locations for log axes     Method resolution order: LogLocator Locator TickHelper Methods defined here: __call__(self) Return the locations of the ticks __init__(self, base=10.0, subs=[1.0]) place ticks on the location= base**i*subs[j] autoscale(self) Try to choose the view limits intelligently base(self, base) set the base of the log scaling (major tick every base**i, i interger) subs(self, subs) set the minor ticks the log scaling every base**i*subs[j] Methods inherited from Locator: pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class MaxNLocator(Locator)     Select no more than N intervals at nice locations.     Method resolution order: MaxNLocator Locator TickHelper Methods defined here: __call__(self) __init__(self, nbins=10, steps=None, trim=True, integer=False, symmetric=False) autoscale(self) bin_boundaries(self, vmin, vmax) Methods inherited from Locator: pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class MultipleLocator(Locator)     Set a tick on every integer that is multiple of base in the viewInterval     Method resolution order: MultipleLocator Locator TickHelper Methods defined here: __call__(self) Return the locations of the ticks __init__(self, base=1.0) autoscale(self) Set the view limits to the nearest multiples of base that contain the data Methods inherited from Locator: pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class NullFormatter(Formatter)     Always return the empty string     Method resolution order: NullFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos Methods inherited from Formatter: fix_minus(self, s) some classes may want to replace a hyphen for minus with the proper unicode symbol as described here     http://sourceforge.net/tracker/index.php?func=detail&aid=1962574&group_id=80706&atid=560720. The default is to do nothing   Note, if you use this method, eg in format_data or call, you probably don't want to use it for format_data_short since the toolbar uses this for interative coord reporting and I doubt we can expect GUIs across platforms will handle the unicode correctly.  So for now the classes that override fix_minus should have an explicit format_data_short method format_data(self, value) format_data_short(self, value) return a short string version get_offset(self) set_locs(self, locs) Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class NullLocator(Locator)     No ticks     Method resolution order: NullLocator Locator TickHelper Methods defined here: __call__(self) Return the locations of the ticks Methods inherited from Locator: autoscale(self) autoscale the view limits pan(self, numsteps) Pan numticks (can be positive or negative) refresh(self) refresh internal information based on current lim zoom(self, direction) Zoom in/out on axis; if direction is >0 zoom in, else zoom out Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class ScalarFormatter(Formatter)     Tick location is a plain old number.  If useOffset==True and the data range is much smaller than the data average, then an offset will be determined such that the tick labels are meaningful. Scientific notation is used for data < 1e-3 or data >= 1e4.     Method resolution order: ScalarFormatter Formatter TickHelper Methods defined here: __call__(self, x, pos=None) Return the format for tick val x at position pos __init__(self, useOffset=True, useMathText=False) fix_minus(self, s) use a unicode minus rather than hyphen format_data(self, value) return a formatted string representation of a number format_data_short(self, value) return a short formatted string representation of a number get_offset(self) Return scientific notation, plus offset pprint_val(self, x) set_locs(self, locs) set the locations of the ticks set_powerlimits(self, lims) Sets size thresholds for scientific notation.   e.g. xaxis.set_powerlimits((-3, 4)) sets the pre-2007 default in which scientific notation is used for numbers less than 1e-3 or greater than 1e4. See also set_scientific(). set_scientific(self, b) True or False to turn scientific notation on or off see also set_powerlimits() Data and other attributes inherited from Formatter: locs = [] Methods inherited from TickHelper: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes inherited from TickHelper: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None   class TickHelper       Methods defined here: create_dummy_axis(self) set_axis(self, axis) set_bounds(self, vmin, vmax) set_data_interval(self, vmin, vmax) set_view_interval(self, vmin, vmax) Data and other attributes defined here: DummyAxis = <class matplotlib.ticker.DummyAxis at 0xeaeef0> axis = None

Data
		__all__ = ('TickHelper', 'Formatter', 'FixedFormatter', 'NullFormatter', 'FuncFormatter', 'FormatStrFormatter', 'ScalarFormatter', 'LogFormatter', 'LogFormatterExponent', 'LogFormatterMathtext', 'Locator', 'IndexLocator', 'FixedLocator', 'NullLocator', 'LinearLocator', 'LogLocator', 'AutoLocator', 'MultipleLocator', 'MaxNLocator')