plot.py

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#-----------------------------------------------------------------------------
# Name:        wx.lib.plot.py
# Purpose:     Line, Bar and Scatter Graphs
#
# Author:      Gordon Williams
#
# Created:     2003/11/03
# RCS-ID:      $Id: plot.py 8707 2008-06-25 20:12:06Z jcorgan $
# Copyright:   (c) 2002,2007
# Licence:     Use as you wish.
#-----------------------------------------------------------------------------
# 12/15/2003 - Jeff Grimmett ([e-mail])
#
# o 2.5 compatability update.
# o Renamed to plot.py in the wx.lib directory.
# o Reworked test frame to work with wx demo framework. This saves a bit
#   of tedious cut and paste, and the test app is excellent.
#
# 12/18/2003 - Jeff Grimmett ([e-mail])
#
# o wxScrolledMessageDialog -> ScrolledMessageDialog
#
# Oct 6, 2004  Gordon Williams ([e-mail])
#   - Added bar graph demo
#   - Modified line end shape from round to square.
#   - Removed FloatDCWrapper for conversion to ints and ints in arguments
#
# Oct 15, 2004  Gordon Williams ([e-mail])
#   - Imported modules given leading underscore to name.
#   - Added Cursor Line Tracking and User Point Labels. 
#   - Demo for Cursor Line Tracking and Point Labels.
#   - Size of plot preview frame adjusted to show page better.
#   - Added helper functions PositionUserToScreen and PositionScreenToUser in PlotCanvas.
#   - Added functions GetClosestPoints (all curves) and GetClosestPoint (only closest curve)
#       can be in either user coords or screen coords.
#   
# May 27, 2007 Johnathan Corgan ([e-mail])
#   - Converted from numarray to numpy

"""
This is a simple light weight plotting module that can be used with
Boa or easily integrated into your own wxPython application.  The
emphasis is on small size and fast plotting for large data sets.  It
has a reasonable number of features to do line and scatter graphs
easily as well as simple bar graphs.  It is not as sophisticated or 
as powerful as SciPy Plt or Chaco.  Both of these are great packages 
but consume huge amounts of computer resources for simple plots.
They can be found at http://scipy.com

This file contains two parts; first the re-usable library stuff, then,
after a "if __name__=='__main__'" test, a simple frame and a few default
plots for examples and testing.

Based on wxPlotCanvas
Written by K.Hinsen, R. Srinivasan;
Ported to wxPython Harm van der Heijden, feb 1999

Major Additions Gordon Williams Feb. 2003 ([e-mail])
    -More style options
    -Zooming using mouse 'rubber band'
    -Scroll left, right
    -Grid(graticule)
    -Printing, preview, and page set up (margins)
    -Axis and title labels
    -Cursor xy axis values
    -Doc strings and lots of comments
    -Optimizations for large number of points
    -Legends
    
Did a lot of work here to speed markers up. Only a factor of 4
improvement though. Lines are much faster than markers, especially
filled markers.  Stay away from circles and triangles unless you
only have a few thousand points.

Times for 25,000 points
Line - 0.078 sec
Markers
Square -                   0.22 sec
dot -                      0.10
circle -                   0.87
cross,plus -               0.28
triangle, triangle_down -  0.90

Thanks to Chris Barker for getting this version working on Linux.

Zooming controls with mouse (when enabled):
    Left mouse drag - Zoom box.
    Left mouse double click - reset zoom.
    Right mouse click - zoom out centred on click location.
"""

import  string as _string
import  time as _time
import  wx

# Needs numpy or numarray
try:
    import numpy as _numpy
except:
    try:
        import numarray as _numpy  #if numarray is used it is renamed numpy
    except:
        msg= """
        This module requires the numpy or numarray module,
        which could not be imported.  It probably is not installed
        (it's not part of the standard Python distribution). See the
        Python site (http://www.python.org) for information on
        downloading source or binaries."""
        raise ImportError, "numpy or numarray not found. \n" + msg



#
# Plotting classes...
#
class PolyPoints:
    """Base Class for lines and markers
        - All methods are private.
    """

    def __init__(self, points, attr):
        self.points = _numpy.array(points)
        self.currentScale= (1,1)
        self.currentShift= (0,0)
        self.scaled = self.points
        self.attributes = {}
        self.attributes.update(self._attributes)
        for name, value in attr.items():   
            if name not in self._attributes.keys():
                raise KeyError, "Style attribute incorrect. Should be one of %s" % self._attributes.keys()
            self.attributes[name] = value
        
    def boundingBox(self):
        if len(self.points) == 0:
            # no curves to draw
            # defaults to (-1,-1) and (1,1) but axis can be set in Draw
            minXY= _numpy.array([-1,-1])
            maxXY= _numpy.array([ 1, 1])
        else:
            minXY= _numpy.minimum.reduce(self.points)
            maxXY= _numpy.maximum.reduce(self.points)
        return minXY, maxXY

    def scaleAndShift(self, scale=(1,1), shift=(0,0)):
        if len(self.points) == 0:
            # no curves to draw
            return
        if (scale is not self.currentScale) or (shift is not self.currentShift):
            # update point scaling
            self.scaled = scale*self.points+shift
            self.currentScale= scale
            self.currentShift= shift
        # else unchanged use the current scaling
        
    def getLegend(self):
        return self.attributes['legend']

    def getClosestPoint(self, pntXY, pointScaled= True):
        """Returns the index of closest point on the curve, pointXY, scaledXY, distance
            x, y in user coords
            if pointScaled == True based on screen coords
            if pointScaled == False based on user coords
        """
        if pointScaled == True:
            #Using screen coords
            p = self.scaled
            pxy = self.currentScale * _numpy.array(pntXY)+ self.currentShift
        else:
            #Using user coords
            p = self.points
            pxy = _numpy.array(pntXY)
        #determine distance for each point
        d= _numpy.sqrt(_numpy.add.reduce((p-pxy)**2,1)) #sqrt(dx^2+dy^2)
        pntIndex = _numpy.argmin(d)
        dist = d[pntIndex]
        return [pntIndex, self.points[pntIndex], self.scaled[pntIndex], dist]
        
        
class PolyLine(PolyPoints):
    """Class to define line type and style
        - All methods except __init__ are private.
    """
    
    _attributes = {'colour': 'black',
                   'width': 1,
                   'style': wx.SOLID,
                   'legend': ''}

    def __init__(self, points, **attr):
        """Creates PolyLine object
            points - sequence (array, tuple or list) of (x,y) points making up line
            **attr - key word attributes
                Defaults:
                    'colour'= 'black',          - wx.Pen Colour any wx.NamedColour
                    'width'= 1,                 - Pen width
                    'style'= wx.SOLID,          - wx.Pen style
                    'legend'= ''                - Line Legend to display
        """
        PolyPoints.__init__(self, points, attr)

    def draw(self, dc, printerScale, coord= None):
        colour = self.attributes['colour']
        width = self.attributes['width'] * printerScale
        style= self.attributes['style']
        pen = wx.Pen(wx.NamedColour(colour), width, style)
        pen.SetCap(wx.CAP_BUTT)
        dc.SetPen(pen)
        if coord == None:
            dc.DrawLines(self.scaled)
        else:
            dc.DrawLines(coord) # draw legend line

    def getSymExtent(self, printerScale):
        """Width and Height of Marker"""
        h= self.attributes['width'] * printerScale
        w= 5 * h
        return (w,h)


class PolyMarker(PolyPoints):
    """Class to define marker type and style
        - All methods except __init__ are private.
    """
  
    _attributes = {'colour': 'black',
                   'width': 1,
                   'size': 2,
                   'fillcolour': None,
                   'fillstyle': wx.SOLID,
                   'marker': 'circle',
                   'legend': ''}

    def __init__(self, points, **attr):
        """Creates PolyMarker object
        points - sequence (array, tuple or list) of (x,y) points
        **attr - key word attributes
            Defaults:
                'colour'= 'black',          - wx.Pen Colour any wx.NamedColour
                'width'= 1,                 - Pen width
                'size'= 2,                  - Marker size
                'fillcolour'= same as colour,      - wx.Brush Colour any wx.NamedColour
                'fillstyle'= wx.SOLID,      - wx.Brush fill style (use wx.TRANSPARENT for no fill)
                'marker'= 'circle'          - Marker shape
                'legend'= ''                - Marker Legend to display
              
            Marker Shapes:
                - 'circle'
                - 'dot'
                - 'square'
                - 'triangle'
                - 'triangle_down'
                - 'cross'
                - 'plus'
        """
      
        PolyPoints.__init__(self, points, attr)

    def draw(self, dc, printerScale, coord= None):
        colour = self.attributes['colour']
        width = self.attributes['width'] * printerScale
        size = self.attributes['size'] * printerScale
        fillcolour = self.attributes['fillcolour']
        fillstyle = self.attributes['fillstyle']
        marker = self.attributes['marker']

        dc.SetPen(wx.Pen(wx.NamedColour(colour), width))
        if fillcolour:
            dc.SetBrush(wx.Brush(wx.NamedColour(fillcolour),fillstyle))
        else:
            dc.SetBrush(wx.Brush(wx.NamedColour(colour), fillstyle))
        if coord == None:
            self._drawmarkers(dc, self.scaled, marker, size)
        else:
            self._drawmarkers(dc, coord, marker, size) # draw legend marker

    def getSymExtent(self, printerScale):
        """Width and Height of Marker"""
        s= 5*self.attributes['size'] * printerScale
        return (s,s)

    def _drawmarkers(self, dc, coords, marker,size=1):
        f = eval('self._' +marker)
        f(dc, coords, size)

    def _circle(self, dc, coords, size=1):
        fact= 2.5*size
        wh= 5.0*size
        rect= _numpy.zeros((len(coords),4),_numpy.float)+[0.0,0.0,wh,wh]
        rect[:,0:2]= coords-[fact,fact]
        dc.DrawEllipseList(rect.astype(_numpy.int32))

    def _dot(self, dc, coords, size=1):
        dc.DrawPointList(coords)

    def _square(self, dc, coords, size=1):
        fact= 2.5*size
        wh= 5.0*size
        rect= _numpy.zeros((len(coords),4),_numpy.float)+[0.0,0.0,wh,wh]
        rect[:,0:2]= coords-[fact,fact]
        dc.DrawRectangleList(rect.astype(_numpy.int32))

    def _triangle(self, dc, coords, size=1):
        shape= [(-2.5*size,1.44*size), (2.5*size,1.44*size), (0.0,-2.88*size)]
        poly= _numpy.repeat(coords,3)
        poly.shape= (len(coords),3,2)
        poly += shape
        dc.DrawPolygonList(poly.astype(_numpy.int32))

    def _triangle_down(self, dc, coords, size=1):
        shape= [(-2.5*size,-1.44*size), (2.5*size,-1.44*size), (0.0,2.88*size)]
        poly= _numpy.repeat(coords,3)
        poly.shape= (len(coords),3,2)
        poly += shape
        dc.DrawPolygonList(poly.astype(_numpy.int32))
      
    def _cross(self, dc, coords, size=1):
        fact= 2.5*size
        for f in [[-fact,-fact,fact,fact],[-fact,fact,fact,-fact]]:
            lines= _numpy.concatenate((coords,coords),axis=1)+f
            dc.DrawLineList(lines.astype(_numpy.int32))

    def _plus(self, dc, coords, size=1):
        fact= 2.5*size
        for f in [[-fact,0,fact,0],[0,-fact,0,fact]]:
            lines= _numpy.concatenate((coords,coords),axis=1)+f
            dc.DrawLineList(lines.astype(_numpy.int32))

class PlotGraphics:
    """Container to hold PolyXXX objects and graph labels