#!/usr/bin/env python
# The Python version of qwt-*/examples/bode
# To get an impression of the expressive power of Numeric,
# compare the Python and C++ versions of recalc()
import sys
from qt import *
from qwt import *
from Numeric import *
print_xpm = ['32 32 12 1',
'a c #ffffff',
'h c #ffff00',
'c c #ffffff',
'f c #dcdcdc',
'b c #c0c0c0',
'j c #a0a0a4',
'e c #808080',
'g c #808000',
'd c #585858',
'i c #00ff00',
'# c #000000',
'. c None',
'................................',
'................................',
'...........###..................',
'..........#abb###...............',
'.........#aabbbbb###............',
'.........#ddaaabbbbb###.........',
'........#ddddddaaabbbbb###......',
'.......#deffddddddaaabbbbb###...',
'......#deaaabbbddddddaaabbbbb###',
'.....#deaaaaaaabbbddddddaaabbbb#',
'....#deaaabbbaaaa#ddedddfggaaad#',
'...#deaaaaaaaaaa#ddeeeeafgggfdd#',
'..#deaaabbbaaaa#ddeeeeabbbbgfdd#',
'.#deeefaaaaaaa#ddeeeeabbhhbbadd#',
'#aabbbeeefaaa#ddeeeeabbbbbbaddd#',
'#bbaaabbbeee#ddeeeeabbiibbadddd#',
'#bbbbbaaabbbeeeeeeabbbbbbaddddd#',
'#bjbbbbbbaaabbbbeabbbbbbadddddd#',
'#bjjjjbbbbbbaaaeabbbbbbaddddddd#',
'#bjaaajjjbbbbbbaaabbbbadddddddd#',
'#bbbbbaaajjjbbbbbbaaaaddddddddd#',
'#bjbbbbbbaaajjjbbbbbbddddddddd#.',
'#bjjjjbbbbbbaaajjjbbbdddddddd#..',
'#bjaaajjjbbbbbbjaajjbddddddd#...',
'#bbbbbaaajjjbbbjbbaabdddddd#....',
'###bbbbbbaaajjjjbbbbbddddd#.....',
'...###bbbbbbaaajbbbbbdddd#......',
'......###bbbbbbjbbbbbddd#.......',
'.........###bbbbbbbbbdd#........',
'............###bbbbbbd#.........',
'...............###bbb#..........',
'..................###...........']
zoom_xpm = ['32 32 8 1',
'# c #000000',
'b c #c0c0c0',
'a c #ffffff',
'e c #585858',
'd c #a0a0a4',
'c c #0000ff',
'f c #00ffff',
'. c None',
'..######################........',
'.#a#baaaaaaaaaaaaaaaaaa#........',
'#aa#baaaaaaaaaaaaaccaca#........',
'####baaaaaaaaaaaaaaaaca####.....',
'#bbbbaaaaaaaaaaaacccaaa#da#.....',
'#aaaaaaaaaaaaaaaacccaca#da#.....',
'#aaaaaaaaaaaaaaaaaccaca#da#.....',
'#aaaaaaaaaabe###ebaaaaa#da#.....',
'#aaaaaaaaa#########aaaa#da#.....',
'#aaaaaaaa###dbbbb###aaa#da#.....',
'#aaaaaaa###aaaaffb###aa#da#.....',
'#aaaaaab##aaccaaafb##ba#da#.....',
'#aaaaaae#daaccaccaad#ea#da#.....',
'#aaaaaa##aaaaaaccaab##a#da#.....',
'#aaaaaa##aacccaaaaab##a#da#.....',
'#aaaaaa##aaccccaccab##a#da#.....',
'#aaaaaae#daccccaccad#ea#da#.....',
'#aaaaaab##aacccaaaa##da#da#.....',
'#aaccacd###aaaaaaa###da#da#.....',
'#aaaaacad###daaad#####a#da#.....',
'#acccaaaad##########da##da#.....',
'#acccacaaadde###edd#eda#da#.....',
'#aaccacaaaabdddddbdd#eda#a#.....',
'#aaaaaaaaaaaaaaaaaadd#eda##.....',
'#aaaaaaaaaaaaaaaaaaadd#eda#.....',
'#aaaaaaaccacaaaaaaaaadd#eda#....',
'#aaaaaaaaaacaaaaaaaaaad##eda#...',
'#aaaaaacccaaaaaaaaaaaaa#d#eda#..',
'########################dd#eda#.',
'...#dddddddddddddddddddddd##eda#',
'...#aaaaaaaaaaaaaaaaaaaaaa#.####',
'...########################..##.']
class PrintFilter(QwtPlotPrintFilter):
def __init__(self):
QwtPlotPrintFilter.__init__(self)
# __init___()
def color(self, c, item, i):
if not (self.options() & QwtPlotPrintFilter.PrintCanvasBackground):
if item == QwtPlotPrintFilter.MajorGrid:
return Qt.darkGray
elif item == QwtPlotPrintFilter.MinorGrid:
return Qt.gray
if item == QwtPlotPrintFilter.Title:
return Qt.red
elif item == QwtPlotPrintFilter.AxisScale:
return Qt.green
elif item == QwtPlotPrintFilter.AxisTitle:
return Qt.blue
return c
# color()
def font(self, f, item, i):
result = QFont(f)
result.setPointSize(int(f.pointSize()*1.25))
return result
# font()
# class PrintFilter
class BodePlot(QwtPlot):
def __init__(self, *args):
QwtPlot.__init__(self, *args)
self.setTitle('Frequency Response of a 2<sup>nd</sup>-order System')
self.setCanvasBackground(Qt.darkBlue)
# legend
self.setAutoLegend(True)
self.enableLegend(True)
self.setLegendPos(Qwt.Bottom)
self.setLegendFrameStyle(QFrame.Box | QFrame.Sunken)
# grid
self.enableGridXMin()
self.setGridMajPen(QPen(Qt.white, 0, Qt.DotLine))
self.setGridMinPen(QPen(Qt.gray, 0 , Qt.DotLine))
# axes
self.enableAxis(QwtPlot.yRight)
self.setAxisTitle(QwtPlot.xBottom, u'\u03c9/\u03c9<sub>0</sub>')
self.setAxisTitle(QwtPlot.yLeft, 'Amplitude [dB]')
self.setAxisTitle(QwtPlot.yRight, u'Phase [\u00b0]')
self.setAxisOptions(QwtPlot.xBottom, QwtAutoScale.Logarithmic)
self.setAxisMaxMajor(QwtPlot.xBottom, 6)
self.setAxisMaxMinor(QwtPlot.xBottom, 10)
# curves
self.curve1 = self.insertCurve('Amplitude')
self.setCurvePen(self.curve1, QPen(Qt.yellow))
self.setCurveYAxis(self.curve1, QwtPlot.yLeft)
self.curve2 = self.insertCurve('Phase')
self.setCurvePen(self.curve2, QPen(Qt.cyan))
self.setCurveYAxis(self.curve2, QwtPlot.yRight)
# alias
fn = self.fontInfo().family()
# marker
self.mrk1 = self.insertMarker()
self.setMarkerLineStyle(self.mrk1, QwtMarker.VLine)
self.setMarkerPos(self.mrk1, 0.0, 0.0)
self.setMarkerLinePen(self.mrk1, QPen(Qt.green, 2, Qt.DashDotLine))
self.setMarkerLabelAlign(self.mrk1, Qt.AlignRight | Qt.AlignBottom)
self.setMarkerLabel(self.mrk1, '', QFont(fn, 12, QFont.Bold),
Qt.green, QPen(Qt.NoPen), QBrush(Qt.red))
self.mrk2 = self.insertLineMarker('', QwtPlot.yLeft)
self.setMarkerLinePen(self.mrk2, QPen(Qt.red, 2, Qt.DashDotLine))
self.setMarkerLabelAlign(self.mrk2, Qt.AlignRight | Qt.AlignBottom)
self.setMarkerLabel(self.mrk2, '', QFont(fn, 12, QFont.Bold),
Qt.red, QPen(Qt.NoPen),
QBrush(self.canvasBackground()))
self.setMarkerSymbol(self.mrk2, QwtSymbol(
QwtSymbol.Diamond, QBrush(Qt.yellow), QPen(Qt.green), QSize(7,7)))
# text marker
m = self.insertMarker()
self.setMarkerPos(m, 0.1, -20.0)
self.setMarkerLabelAlign(m, Qt.AlignRight | Qt.AlignBottom)
self.setMarkerLabel(
m,
QString(u'[1-(\u03c9/\u03c9<sub>0</sub>)<sup>2</sup>+2j\u03c9/Q]'
'<sup>-1</sup>'),
QFont(fn, 12, QFont.Bold, False),
Qt.blue, QPen(Qt.red, 2), QBrush(Qt.yellow))
self.setDamp(0.01)
# __init__()
def setDamp(self, d):
self.damping = d
# Numerical Python: f, g, a and p are arrays!
f = exp(log(10.0)*arrayrange(-2, 2.02, 0.04))
g = 1.0/(1.0-f*f+2j*self.damping*f)
a = 20.0*log10(abs(g))
p = 180*arctan2(g.imag, g.real)/pi
self.setCurveData(self.curve1, f, a)
self.setCurveData(self.curve2, f, p)
# show3dB and showPeak
i3 = argmax(where(less(a, -3.0), a, -100.0))
f3 = f[i3] - (a[i3]+3.0)*(f[i3]-f[i3-1])/(a[i3]-a[i3-1])
self.setMarkerPos(self.mrk1, f3, 0.0)
self.setMarkerLabelText(self.mrk1, '-3 dB at f = %4g' % f3)
imax = argmax(a)
self.setMarkerPos(self.mrk2, f[imax], a[imax])
self.setMarkerLabelText(self.mrk2, 'Peak: %4g dB' % a[imax])
self.replot()
# setDamp()
# class BodePlot
class BodeDemo(QMainWindow):
def __init__(self, *args):
apply(QMainWindow.__init__, (self,) + args)
self.plot = BodePlot(self)
self.plot.setMargin(5)
self.zoomers = []
zoomer = QwtPlotZoomer(QwtPlot.xBottom,
QwtPlot.yLeft,
QwtPicker.DragSelection,
QwtPicker.AlwaysOff,
self.plot.canvas())
zoomer.setRubberBandPen(QPen(Qt.green))
self.zoomers.append(zoomer)
zoomer = QwtPlotZoomer(QwtPlot.xTop,
QwtPlot.yRight,
QwtPicker.DragSelection,
QwtPicker.AlwaysOff,
self.plot.canvas())
zoomer.setRubberBand(QwtPicker.NoRubberBand)
self.zoomers.append(zoomer)
self.picker = QwtPlotPicker(
QwtPlot.xBottom,
QwtPlot.yLeft,
QwtPicker.PointSelection | QwtPicker.DragSelection,
QwtPlotPicker.CrossRubberBand,
QwtPicker.AlwaysOn,
self.plot.canvas())
self.picker.setRubberBandPen(QPen(Qt.green))
self.picker.setCursorLabelPen(QPen(Qt.cyan))
self.setCentralWidget(self.plot)
self.toolBar = QToolBar(self)
btnZoom = QToolButton(self.toolBar)
btnZoom.setTextLabel("Zoom")
btnZoom.setPixmap(QPixmap(zoom_xpm))
btnZoom.setToggleButton(True)
btnZoom.setUsesTextLabel(True)
btnPrint = QToolButton(self.toolBar)
btnPrint.setTextLabel("Print")
btnPrint.setPixmap(QPixmap(print_xpm))
btnPrint.setUsesTextLabel(True)
self.toolBar.setStretchableWidget(QWidget(self.toolBar))
dampBox = QHBox(self.toolBar)
dampBox.setSpacing(10)
QLabel("Damping Factor", dampBox)
self.cntDamp = QwtCounter(dampBox)
self.cntDamp.setRange(0.01, 5.0, 0.01)
self.cntDamp.setValue(0.01)
self.statusBar()
self.zoom(False)
self.connect(self.cntDamp, SIGNAL('valueChanged(double)'),
self.plot.setDamp)
self.connect(btnPrint, SIGNAL('clicked()'),
self.printPlot)
self.connect(btnZoom, SIGNAL('toggled(bool)'),
self.zoom)
self.connect(self.picker, SIGNAL('moved(const QPoint &)'), self.moved)
self.connect(self.picker, SIGNAL('selected(const QPointArray &)'),
self.selected)
# __init__()
def printPlot(self):
try:
printer = QPrinter(QPrinter.HighResolution)
except AttributeError:
printer = QPrinter()
printer.setOrientation(QPrinter.Landscape)
printer.setColorMode(QPrinter.Color)
printer.setOutputToFile(True)
printer.setOutputFileName('bode-example-%s.ps' % qVersion())
if printer.setup():
filter = PrintFilter()
if (QPrinter.GrayScale == printer.colorMode()):
filter.setOptions(QwtPlotPrintFilter.PrintAll
& ~QwtPlotPrintFilter.PrintCanvasBackground)
self.plot.printPlot(printer, filter)
# printPlot()
def zoom(self, on):
self.zoomers[0].setEnabled(on)
self.zoomers[0].zoom(0)
self.zoomers[1].setEnabled(on)
self.zoomers[1].zoom(0)
if on:
self.picker.setRubberBand(QwtPicker.NoRubberBand)
else:
self.picker.setRubberBand(QwtPicker.CrossRubberBand)
self.showInfo()
# zoom()
def moved(self, point):
info = "Freq=%g, Ampl=%g, Phase=%g" % (
self.plot.invTransform(QwtPlot.xBottom, point.x()),
self.plot.invTransform(QwtPlot.yLeft, point.y()),
self.plot.invTransform(QwtPlot.yRight, point.y()))
self.showInfo(info)
# moved()
def selected(self, points):
self.showInfo()
# selected()
def showInfo(self, text=None):
if text:
self.statusBar().message(text)
elif self.picker.rubberBand():
self.statusBar().message(
'Cursor Pos: Press left mouse button in plot region')
else:
self.statusBar().message(
'Zoom: Press mouse button and drag')
# showInfo()
# class BodeDemo
def main(args):
app = QApplication(args)
fonts = QFontDatabase()
if QString('Verdana') in fonts.families():
app.setFont(QFont('Verdana'))
demo = make()
app.setMainWidget(demo)
app.exec_loop()
def make():
demo = BodeDemo()
demo.resize(540, 400)
demo.show()
return demo
# Admire!
if __name__ == '__main__':
main(sys.argv)