plot_data.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

#
# Copyright 2007,2008 Free Software Foundation, Inc.
# 
# This file is part of GNU Radio
# 
# GNU Radio is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3, or (at your option)
# any later version.
# 
# GNU Radio is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING.  If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
# 

try:
    import scipy
except ImportError:
    print "Please install SciPy to run this script (http://www.scipy.org/)"
    raise SystemExit, 1

try:
    from pylab import *
except ImportError:
    print "Please install Matplotlib to run this script (http://matplotlib.sourceforge.net/)"
    raise SystemExit, 1

from optparse import OptionParser

matplotlib.interactive(True)
matplotlib.use('TkAgg')

class plot_data:
    def __init__(self, datatype, filenames, options):
        self.hfile = list()
        self.legend_text = list()
        for f in filenames:
            self.hfile.append(open(f, "r"))
            self.legend_text.append(f)

        self.block_length = options.block
        self.start = options.start
        self.sample_rate = options.sample_rate

        self.datatype = datatype
        self.sizeof_data = datatype().nbytes    # number of bytes per sample in file

        self.axis_font_size = 16
        self.label_font_size = 18
        self.title_font_size = 20
        self.text_size = 22

        # Setup PLOT
        self.fig = figure(1, figsize=(16, 9), facecolor='w')
        rcParams['xtick.labelsize'] = self.axis_font_size
        rcParams['ytick.labelsize'] = self.axis_font_size
        
        self.text_file_pos = figtext(0.10, 0.88, "File Position: ", weight="heavy", size=self.text_size)
        self.text_block    = figtext(0.40, 0.88, ("Block Size: %d" % self.block_length),
                                     weight="heavy", size=self.text_size)
        self.text_sr       = figtext(0.60, 0.88, ("Sample Rate: %.2f" % self.sample_rate),
                                     weight="heavy", size=self.text_size)
        self.make_plots()

        self.button_left_axes = self.fig.add_axes([0.45, 0.01, 0.05, 0.05], frameon=True)
        self.button_left = Button(self.button_left_axes, "<")
        self.button_left_callback = self.button_left.on_clicked(self.button_left_click)

        self.button_right_axes = self.fig.add_axes([0.50, 0.01, 0.05, 0.05], frameon=True)
        self.button_right = Button(self.button_right_axes, ">")
        self.button_right_callback = self.button_right.on_clicked(self.button_right_click)

        self.xlim = self.sp_f.get_xlim()

        self.manager = get_current_fig_manager()
        connect('key_press_event', self.click)
        show()
        
    def get_data(self, hfile):
        self.text_file_pos.set_text("File Position: %d" % (hfile.tell()//self.sizeof_data))
        f = scipy.fromfile(hfile, dtype=self.datatype, count=self.block_length)
        #print "Read in %d items" % len(self.f)
        if(len(f) == 0):
            print "End of File"
        else:
            self.f = f
            self.time = [i*(1/self.sample_rate) for i in range(len(self.f))]
        
    def make_plots(self):
        self.sp_f = self.fig.add_subplot(2,1,1, position=[0.075, 0.2, 0.875, 0.6])
        self.sp_f.set_title(("Amplitude"), fontsize=self.title_font_size, fontweight="bold")
        self.sp_f.set_xlabel("Time (s)", fontsize=self.label_font_size, fontweight="bold")
        self.sp_f.set_ylabel("Amplitude (V)", fontsize=self.label_font_size, fontweight="bold")
        self.plot_f = list()

        maxval = -1e12
        minval = 1e12

        for hf in self.hfile:
            # if specified on the command-line, set file pointer
            hf.seek(self.sizeof_data*self.start, 1)

            self.get_data(hf)
        
            # Subplot for real and imaginary parts of signal
            self.plot_f += plot(self.time, self.f, 'o-')
            maxval = max(maxval, max(self.f))
            minval = min(minval, min(self.f))

        self.sp_f.set_ylim([1.5*minval, 1.5*maxval])

        self.leg = self.sp_f.legend(self.plot_f, self.legend_text)

        draw()

    def update_plots(self):
        maxval = -1e12
        minval = 1e12
        for hf,p in zip(self.hfile,self.plot_f):
            self.get_data(hf)
            p.set_data([self.time, self.f])
            maxval = max(maxval, max(self.f))
            minval = min(minval, min(self.f))

        self.sp_f.set_ylim([1.5*minval, 1.5*maxval])
        
        draw()
        
    def click(self, event):
        forward_valid_keys = [" ", "down", "right"]
        backward_valid_keys = ["up", "left"]

        if(find(event.key, forward_valid_keys)):
            self.step_forward()
            
        elif(find(event.key, backward_valid_keys)):
            self.step_backward()

    def button_left_click(self, event):
        self.step_backward()

    def button_right_click(self, event):
        self.step_forward()

    def step_forward(self):
        self.update_plots()

    def step_backward(self):
        for hf in self.hfile:
            # Step back in file position
            if(hf.tell() >= 2*self.sizeof_data*self.block_length ):
                hf.seek(-2*self.sizeof_data*self.block_length, 1)
            else:
                hf.seek(-hf.tell(),1)
        self.update_plots()
        

def find(item_in, list_search):
    try:
	return list_search.index(item_in) != None
    except ValueError:
	return False