plot.py

这是用python语言写的一个数字广播的信号处理工具包。利用它

        #save for next erase
        self.last_PointLabel = mDataDict

    # event handlers **********************************
    def OnMotion(self, event):
        if self._zoomEnabled and event.LeftIsDown():
            if self._hasDragged:
                self._drawRubberBand(self._zoomCorner1, self._zoomCorner2) # remove old
            else:
                self._hasDragged= True
            self._zoomCorner2[0], self._zoomCorner2[1] = self.GetXY(event)
            self._drawRubberBand(self._zoomCorner1, self._zoomCorner2) # add new

    def OnMouseLeftDown(self,event):
        self._zoomCorner1[0], self._zoomCorner1[1]= self.GetXY(event)

    def OnMouseLeftUp(self, event):
        if self._zoomEnabled:
            if self._hasDragged == True:
                self._drawRubberBand(self._zoomCorner1, self._zoomCorner2) # remove old
                self._zoomCorner2[0], self._zoomCorner2[1]= self.GetXY(event)
                self._hasDragged = False  # reset flag
                minX, minY= _numpy.minimum( self._zoomCorner1, self._zoomCorner2)
                maxX, maxY= _numpy.maximum( self._zoomCorner1, self._zoomCorner2)
                self.last_PointLabel = None        #reset pointLabel
                if self.last_draw != None:
                    self.Draw(self.last_draw[0], xAxis = (minX,maxX), yAxis = (minY,maxY), dc = None)
            #else: # A box has not been drawn, zoom in on a point
            ## this interfered with the double click, so I've disables it.
            #    X,Y = self.GetXY(event)
            #    self.Zoom( (X,Y), (self._zoomInFactor,self._zoomInFactor) )

    def OnMouseDoubleClick(self,event):
        if self._zoomEnabled:
            self.Reset()
        
    def OnMouseRightDown(self,event):
        if self._zoomEnabled:
            X,Y = self.GetXY(event)
            self.Zoom( (X,Y), (self._zoomOutFactor, self._zoomOutFactor) )

    def OnPaint(self, event):
        # All that is needed here is to draw the buffer to screen
        if self.last_PointLabel != None:
            self._drawPointLabel(self.last_PointLabel) #erase old
            self.last_PointLabel = None
        dc = wx.BufferedPaintDC(self, self._Buffer)

    def OnSize(self,event):
        # The Buffer init is done here, to make sure the buffer is always
        # the same size as the Window
        Size  = self.GetClientSize()

        # Make new offscreen bitmap: this bitmap will always have the
        # current drawing in it, so it can be used to save the image to
        # a file, or whatever.
        self._Buffer = wx.EmptyBitmap(Size[0],Size[1])
        self._setSize()

        self.last_PointLabel = None        #reset pointLabel

        if self.last_draw is None:
            self.Clear()
        else:
            graphics, xSpec, ySpec = self.last_draw
            self.Draw(graphics,xSpec,ySpec)

    def OnLeave(self, event):
        """Used to erase pointLabel when mouse outside window"""
        if self.last_PointLabel != None:
            self._drawPointLabel(self.last_PointLabel) #erase old
            self.last_PointLabel = None

        
    # Private Methods **************************************************
    def _setSize(self, width=None, height=None):
        """DC width and height."""
        if width == None:
            (self.width,self.height) = self.GetClientSize()
        else:
            self.width, self.height= width,height    
        self.plotbox_size = 0.97*_numpy.array([self.width, self.height])
        xo = 0.5*(self.width-self.plotbox_size[0])
        yo = self.height-0.5*(self.height-self.plotbox_size[1])
        self.plotbox_origin = _numpy.array([xo, yo])
    
    def _setPrinterScale(self, scale):
        """Used to thicken lines and increase marker size for print out."""
        # line thickness on printer is very thin at 600 dot/in. Markers small
        self.printerScale= scale
     
    def _printDraw(self, printDC):
        """Used for printing."""
        if self.last_draw != None:
            graphics, xSpec, ySpec= self.last_draw
            self.Draw(graphics,xSpec,ySpec,printDC)

    def _drawPointLabel(self, mDataDict):
        """Draws and erases pointLabels"""
        width = self._Buffer.GetWidth()
        height = self._Buffer.GetHeight()
        tmp_Buffer = wx.EmptyBitmap(width,height)
        dcs = wx.MemoryDC()
        dcs.SelectObject(tmp_Buffer)
        dcs.Clear()
        dcs.BeginDrawing()
        self._pointLabelFunc(dcs,mDataDict)  #custom user pointLabel function
        dcs.EndDrawing()

        dc = wx.ClientDC( self )
        #this will erase if called twice
        dc.Blit(0, 0, width, height, dcs, 0, 0, wx.EQUIV)  #(NOT src) XOR dst
        

    def _drawLegend(self,dc,graphics,rhsW,topH,legendBoxWH, legendSymExt, legendTextExt):
        """Draws legend symbols and text"""
        # top right hand corner of graph box is ref corner
        trhc= self.plotbox_origin+ (self.plotbox_size-[rhsW,topH])*[1,-1]
        legendLHS= .091* legendBoxWH[0]  # border space between legend sym and graph box
        lineHeight= max(legendSymExt[1], legendTextExt[1]) * 1.1 #1.1 used as space between lines
        dc.SetFont(self._getFont(self._fontSizeLegend))
        for i in range(len(graphics)):
            o = graphics[i]
            s= i*lineHeight
            if isinstance(o,PolyMarker):
                # draw marker with legend
                pnt= (trhc[0]+legendLHS+legendSymExt[0]/2., trhc[1]+s+lineHeight/2.)
                o.draw(dc, self.printerScale, coord= _numpy.array([pnt]))
            elif isinstance(o,PolyLine):
                # draw line with legend
                pnt1= (trhc[0]+legendLHS, trhc[1]+s+lineHeight/2.)
                pnt2= (trhc[0]+legendLHS+legendSymExt[0], trhc[1]+s+lineHeight/2.)
                o.draw(dc, self.printerScale, coord= _numpy.array([pnt1,pnt2]))
            else:
                raise TypeError, "object is neither PolyMarker or PolyLine instance"
            # draw legend txt
            pnt= (trhc[0]+legendLHS+legendSymExt[0], trhc[1]+s+lineHeight/2.-legendTextExt[1]/2)
            dc.DrawText(o.getLegend(),pnt[0],pnt[1])
        dc.SetFont(self._getFont(self._fontSizeAxis)) # reset

    def _titleLablesWH(self, dc, graphics):
        """Draws Title and labels and returns width and height for each"""
        # TextExtents for Title and Axis Labels
        dc.SetFont(self._getFont(self._fontSizeTitle))
        title= graphics.getTitle()
        titleWH= dc.GetTextExtent(title)
        dc.SetFont(self._getFont(self._fontSizeAxis))
        xLabel, yLabel= graphics.getXLabel(),graphics.getYLabel()
        xLabelWH= dc.GetTextExtent(xLabel)
        yLabelWH= dc.GetTextExtent(yLabel)
        return titleWH, xLabelWH, yLabelWH
    
    def _legendWH(self, dc, graphics):
        """Returns the size in screen units for legend box"""
        if self._legendEnabled != True:
            legendBoxWH= symExt= txtExt= (0,0)
        else:
            # find max symbol size
            symExt= graphics.getSymExtent(self.printerScale)
            # find max legend text extent
            dc.SetFont(self._getFont(self._fontSizeLegend))
            txtList= graphics.getLegendNames()
            txtExt= dc.GetTextExtent(txtList[0])
            for txt in graphics.getLegendNames()[1:]:
                txtExt= _numpy.maximum(txtExt,dc.GetTextExtent(txt))
            maxW= symExt[0]+txtExt[0]    
            maxH= max(symExt[1],txtExt[1])
            # padding .1 for lhs of legend box and space between lines
            maxW= maxW* 1.1
            maxH= maxH* 1.1 * len(txtList)
            dc.SetFont(self._getFont(self._fontSizeAxis))
            legendBoxWH= (maxW,maxH)
        return (legendBoxWH, symExt, txtExt)

    def _drawRubberBand(self, corner1, corner2):
        """Draws/erases rect box from corner1 to corner2"""
        ptx,pty,rectWidth,rectHeight= self._point2ClientCoord(corner1, corner2)
        # draw rectangle
        dc = wx.ClientDC( self )
        dc.BeginDrawing()                 
        dc.SetPen(wx.Pen(wx.BLACK))
        dc.SetBrush(wx.Brush( wx.WHITE, wx.TRANSPARENT ) )
        dc.SetLogicalFunction(wx.INVERT)
        dc.DrawRectangle( ptx,pty, rectWidth,rectHeight)
        dc.SetLogicalFunction(wx.COPY)
        dc.EndDrawing()

    def _getFont(self,size):
        """Take font size, adjusts if printing and returns wx.Font"""
        s = size*self.printerScale
        of = self.GetFont()
        # Linux speed up to get font from cache rather than X font server
        key = (int(s), of.GetFamily (), of.GetStyle (), of.GetWeight ())
        font = self._fontCache.get (key, None)
        if font:
            return font                 # yeah! cache hit
        else:
            font =  wx.Font(int(s), of.GetFamily(), of.GetStyle(), of.GetWeight())
            self._fontCache[key] = font
            return font


    def _point2ClientCoord(self, corner1, corner2):
        """Converts user point coords to client screen int coords x,y,width,height"""
        c1= _numpy.array(corner1)
        c2= _numpy.array(corner2)
        # convert to screen coords
        pt1= c1*self._pointScale+self._pointShift
        pt2= c2*self._pointScale+self._pointShift
        # make height and width positive
        pul= _numpy.minimum(pt1,pt2) # Upper left corner
        plr= _numpy.maximum(pt1,pt2) # Lower right corner
        rectWidth, rectHeight= plr-pul
        ptx,pty= pul
        return ptx, pty, rectWidth, rectHeight 
    
    def _axisInterval(self, spec, lower, upper):
        """Returns sensible axis range for given spec"""
        if spec == 'none' or spec == 'min':
            if lower == upper:
                return lower-0.5, upper+0.5
            else:
                return lower, upper
        elif spec == 'auto':
            range = upper-lower
            # if range == 0.:
            if abs(range) < 1e-36:
                return lower-0.5, upper+0.5
            log = _numpy.log10(range)
            power = _numpy.floor(log)
            fraction = log-power
            if fraction <= 0.05:
                power = power-1
            grid = 10.**power
            lower = lower - lower % grid
            mod = upper % grid
            if mod != 0:
                upper = upper - mod + grid
            return lower, upper
        elif type(spec) == type(()):
            lower, upper = spec
            if lower <= upper:
                return lower, upper
            else:
                return upper, lower
        else:
            raise ValueError, str(spec) + ': illegal axis specification'

    def _drawAxes(self, dc, p1, p2, scale, shift, xticks, yticks):
        
        penWidth= self.printerScale        # increases thickness for printing only
        dc.SetPen(wx.Pen(wx.NamedColour('BLACK'), penWidth))
        
        # set length of tick marks--long ones make grid
        if self._gridEnabled:
            x,y,width,height= self._point2ClientCoord(p1,p2)
            yTickLength= width/2.0 +1
            xTickLength= height/2.0 +1
        else:
            yTickLength= 3 * self.printerScale  # lengthens lines for printing
            xTickLength= 3 * self.printerScale
        
        if self._xSpec is not 'none':
            lower, upper = p1[0],p2[0]
            text = 1
            for y, d in [(p1[1], -xTickLength), (p2[1], xTickLength)]:   # miny, maxy and tick lengths
                a1 = scale*_numpy.array([lower, y])+shift
                a2 = scale*_numpy.array([upper, y])+shift
                dc.DrawLine(a1[0],a1[1],a2[0],a2[1])  # draws upper and lower axis line
                for x, label in xticks:
                    pt = scale*_numpy.array([x, y])+shift
                    dc.DrawLine(pt[0],pt[1],pt[0],pt[1] + d) # draws tick mark d units
                    if text:
                        dc.DrawText(label,pt[0],pt[1])
                text = 0  # axis values not drawn on top side

        if self._ySpec is not 'none':
            lower, upper = p1[1],p2[1]
            text = 1
            h = dc.GetCharHeight()
            for x, d in [(p1[0], -yTickLength), (p2[0], yTickLength)]:
                a1 = scale*_numpy.array([x, lower])+shift
                a2 = scale*_numpy.array([x, upper])+shift
                dc.DrawLine(a1[0],a1[1],a2[0],a2[1])
                for y, label in yticks:
                    pt = scale*_numpy.array([x, y])+shift
                    dc.DrawLine(pt[0],pt[1],pt[0]-d,pt[1])
                    if text:
                        dc.DrawText(label,pt[0]-dc.GetTextExtent(label)[0],
                                    pt[1]-0.5*h)
                text = 0    # axis values not drawn on right side

    def _ticks(self, lower, upper, step=None):
        ideal = (upper-lower)/7.
        log = _numpy.log10(ideal)
        power = _numpy.floor(log)
        fraction = log-power
        factor = 1.
        error = fraction
        for f, lf in self._multiples:
            e = _numpy.fabs(fraction-lf)
            if e < error:
                error = e
                factor = f
        grid = factor * 10.**power
        if power > 4 or power < -4:
            format = '%+7.1e'        
        elif power >= 0:
            digits = max(1, int(power))
            format = '%' + `digits`+'.0f'
        else:
            digits = -int(power)
            format = '%'+`digits+2`+'.'+`digits`+'f'
        #force grid when step is not None
        if step is not None: grid = step
        ticks = []
        t = -grid*_numpy.floor(-lower/grid)
        while t <= upper:
            if t == -0: t = 0 #remove neg zero condition
            ticks.append( (t, format % (t,)) )
            t = t + grid
        return ticks

    def _scope_ticks (self, lower, upper):
        '''Always 10 divisions, no labels'''
        grid = (upper - lower) / 10.0
        ticks = []
        t = lower
        while t <= upper: