def __init__(self):
wx.Frame.__init__(self, None, -1, self.title)
# Set initial time axis length
self.initial_xlen = 3
# Start data generator
self.data = DataGen()
# Create lists to store x and y data
self.xdata = [0]
self.ydata = [0]
self.paused = False
# Create visualiser UI
print "Loading visualiser..."
self.create_menu()
self.create_status_bar()
self.create_main_panel()
# Delay for one second; prevents errors that occur when the
# thread attempts to draw the graph before the UI is fully loaded
time.sleep(1)
print "Opening visualiser..."
# Start timer for refreshing graph
self.start_time = time.time()
# Open thread to continuously redraw graph
Thread(target=self.refresh_graph, args=()).start()
class GraphFrame(wx.Frame):
"""Creates the graph frame and continuously plots the data from the
Arduino board"""
title = 'Arduino Oscilloscope'
def __init__(self):
wx.Frame.__init__(self, None, -1, self.title)
# Set initial time axis length
self.initial_xlen = 3
# Start data generator
self.data = DataGen()
# Create lists to store x and y data
self.xdata = [0]
self.ydata = [0]
self.paused = False
# Create visualiser UI
print "Loading visualiser..."
self.create_menu()
self.create_status_bar()
self.create_main_panel()
# Delay for one second; prevents errors that occur when the
# thread attempts to draw the graph before the UI is fully loaded
time.sleep(1)
print "Opening visualiser..."
# Start timer for refreshing graph
self.start_time = time.time()
# Open thread to continuously redraw graph
Thread(target=self.refresh_graph, args=()).start()
def create_menu(self):
"""Creates a menu with an option to save the plot"""
self.menubar = wx.MenuBar()
# Create save option
menu_file = wx.Menu()
m_expt = menu_file.Append(-1, "&Save plot\tCtrl-S", "Save plot to file")
self.Bind(wx.EVT_MENU, self.on_save_plot, m_expt)
self.menubar.Append(menu_file, "&File")
self.SetMenuBar(self.menubar)
def create_main_panel(self):
"""Creates the aplication's main window"""
self.panel = wx.Panel(self)
# Create graph plot
self.init_plot()
self.canvas = FigCanvas(self.panel, -1, self.fig)
# Create pause button
self.pause_button = wx.Button(self.panel, -1, "Pause")
self.Bind(wx.EVT_BUTTON, self.on_pause_button, self.pause_button)
self.Bind(wx.EVT_UPDATE_UI, self.on_update_pause_button, self.pause_button)
# Create show grid checkbox
self.cb_grid = wx.CheckBox(self.panel, -1,
"Show Grid",
style=wx.ALIGN_RIGHT)
self.Bind(wx.EVT_CHECKBOX, self.on_cb_grid, self.cb_grid)
self.cb_grid.SetValue(True)
# Create box to control length of x axis
self.xlen_control = ControlPanel(self.panel, -1, "x_len", self.initial_xlen)
self.xlen_ctrl_text = wx.StaticText(self.panel, -1, "Set x axis length:")
self.xlen_ctrl_text.SetFont(wx.Font(10,wx.SWISS,wx.NORMAL,wx.BOLD))
self.xlen_ctrl_text.SetSize(self.xlen_ctrl_text.GetBestSize())
# Create boxes to control limits of y axis
self.ymin_control = ControlPanel(self.panel, -1, "y_min", -0.1)
self.ymax_control = ControlPanel(self.panel, -1, "y_max", 5.1)
self.ylim_ctrl_text = wx.StaticText(self.panel, -1, "Set y axis limits:")
self.ylim_ctrl_text.SetFont(wx.Font(10,wx.SWISS,wx.NORMAL,wx.BOLD))
self.ylim_ctrl_text.SetSize(self.ylim_ctrl_text.GetBestSize())
# Set position of UI elements
self.hbox1 = wx.BoxSizer(wx.HORIZONTAL)
self.hbox1.Add(self.pause_button, border=5, flag=wx.ALL | wx.ALIGN_CENTER_VERTICAL)
self.hbox1.AddSpacer(20)
self.hbox1.Add(self.cb_grid, border=5, flag=wx.ALL | wx.ALIGN_CENTER_VERTICAL)
self.hbox1.AddSpacer(20)
self.hbox1.Add(self.xlen_ctrl_text,0,wx.ALL,10)
self.hbox1.Add(self.xlen_control, border=5, flag=wx.ALL | wx.ALIGN_CENTER_VERTICAL)
self.hbox1.AddSpacer(20)
self.hbox1.Add(self.ylim_ctrl_text,0,wx.ALL,10)
self.hbox1.Add(self.ymin_control, border=5, flag=wx.ALL | wx.ALIGN_CENTER_VERTICAL)
self.hbox1.Add(self.ymax_control, border=5, flag=wx.ALL | wx.ALIGN_CENTER_VERTICAL)
self.vbox = wx.BoxSizer(wx.VERTICAL)
self.vbox.Add(self.canvas, 1, flag=wx.LEFT | wx.TOP | wx.GROW)
self.vbox.Add(self.hbox1, 0, flag=wx.ALIGN_LEFT | wx.TOP)
self.panel.SetSizer(self.vbox)
self.vbox.Fit(self)
def create_status_bar(self):
self.statusbar = self.CreateStatusBar()
def init_plot(self):
"""Initialises the graph plot"""
self.dpi = 100
self.fig = Figure((10.0, 5.0), dpi=self.dpi)
self.axes = self.fig.add_subplot(111)
self.axes.set_axis_bgcolor('black')
self.axes.set_title('Arduino Oscilloscope Data', size=12)
self.axes.set_xlabel('Time /s', size=10)
self.axes.set_ylabel('Voltage /V', size=10)
pylab.setp(self.axes.get_xticklabels(), fontsize=8)
pylab.setp(self.axes.get_yticklabels(), fontsize=8)
# Plot data as a line
self.plot_data = self.axes.plot(
self.xdata,self.ydata,
linewidth=1,
color=(1, 1, 0),
)[0]
def draw_plot(self):
"""Re-draws the graph plot."""
# Obtain manually set value for x axis length
try:
x_len = float(self.xlen_control.manual_value())
except ValueError:
x_len = self.initial_xlen
# Set maximum x axis value equal to maximum x point,
# with x axis length equal to x_len
t_max = self.xdata[-1]
if t_max > x_len:
xmax = t_max
xmin = t_max - x_len
else:
xmax = x_len
xmin = 0
# Obtain manually set values for y axis limits
try:
ymax = float(self.ymax_control.manual_value())
except ValueError:
ymax = 5.5
try:
ymin = float(self.ymin_control.manual_value())
except ValueError:
ymin = -0.5
# Set graph boundaries
self.axes.set_xbound(lower=xmin, upper=xmax)
self.axes.set_ybound(lower=ymin, upper=ymax)
# Draws grid if "Show grid" is checked
if self.cb_grid.IsChecked():
self.axes.grid(True, color='gray')
else:
self.axes.grid(False)
# Set x and y data
self.plot_data.set_xdata(self.xdata)
self.plot_data.set_ydata(self.ydata)
# Redraw the plot
self.canvas.draw()
def on_pause_button(self, event):
self.paused = not self.paused
def on_update_pause_button(self, event):
label = "Resume" if self.paused else "Pause"
self.pause_button.SetLabel(label)
def on_cb_grid(self, event):
self.draw_plot()
def on_cb_xlab(self, event):
self.draw_plot()
def on_save_plot(self, event):
file_choices = "PNG (*.png)|*.png"
dlg = wx.FileDialog(
self,
message="Save plot as...",
defaultDir=os.getcwd(),
defaultFile="plot.png",
wildcard=file_choices,
style=wx.SAVE)
if dlg.ShowModal() == wx.ID_OK:
path = dlg.GetPath()
self.canvas.print_figure(path, dpi=self.dpi)
self.flash_status_message("Saved to %s" % path)
def refresh_graph(self):
"""Pulls new data from the interfacer and re-draws the plot."""
while True:
# if paused do not add data, but still redraw the plot
# (to respond to manual control changes)
if not self.paused:
# Pull the data from the interfacer data buffer
y_buffer_draw = self.data.get_data()
# Calculate length of data buffer
y_len = len(y_buffer_draw)
# Only attempt to update data if there is new data
if not y_len == 0:
# Calculate the time difference from last redraw,
# and estimate time values for each y data point
current_time = time.time() - self.start_time
last_time = self.xdata[-1]
t_int = (current_time - last_time) / y_len
# Add new data values to data lists
for y in y_buffer_draw:
self.ydata.append(y)
x_buffer_draw = np.arange(last_time + t_int,
current_time + t_int,
t_int)
for x in x_buffer_draw:
self.xdata.append(x)
# Correct length of data lists if there is a difference
if len(self.ydata) > len(self.xdata):
lendiff = len(self.ydata) - len(self.xdata)
del self.ydata[0:lendiff]
if len(self.xdata) > len(self.ydata):
lendiff = len(self.xdata) - len(self.ydata)
del self.xdata[0:lendiff]
# Limit length of data lists to maintain performance
if len(self.xdata) > 10000:
self.xdata = self.xdata[-10000:-1]
self.ydata = self.ydata[-10000:-1]
# Redraw the plot
self.draw_plot()
def flash_status_message(self, msg, flash_len_ms=1500):
self.statusbar.SetStatusText(msg)
self.timeroff = wx.Timer(self)
self.Bind(
wx.EVT_TIMER,
self.on_flash_status_off,
self.timeroff)
self.timeroff.Start(flash_len_ms, oneShot=True)
def on_flash_status_off(self, event):
self.statusbar.SetStatusText('')
