MAVExplorer: Add histrograms

MAVProxy/modules/lib/graph_ui.py

@@ -78,3 +78,53 @@ def set_xlim(self, xlim):
                 return False
             self.xlim = xlim
         return True
+
+
+class Histogram_UI(object):
+    '''UI class for displaying histograms from log data'''
+
+    def __init__(self, mestate):
+        self.mestate = mestate
+        self.xlim = None
+        self.xlim_pipe = multiproc.Pipe()
+
+    def display_histogram(self, graphdef, bins=50, show_stats=True):
+        '''display a histogram'''
+        if 'mestate' in globals():
+            self.mestate.console.write("Histogram: %s\n" % ' '.join(graphdef.expression.split()))
+        else:
+            self.mestate.child_pipe_send_console.send("Histogram: %s\n" % ' '.join(graphdef.expression.split()))
+
+        mh = grapher.MavHistogram()
+        if self.mestate.settings.title is not None:
+            mh.set_title(self.mestate.settings.title)
+        else:
+            mh.set_title(graphdef.name)
+        mh.set_bins(bins)
+        mh.set_show_stats(show_stats)
+        mh.set_condition(self.mestate.settings.condition)
+        mh.set_legend(self.mestate.settings.legend)
+        mh.add_mav(copy.copy(self.mestate.mlog))
+        for f in graphdef.expression.split():
+            mh.add_field(f)
+        mh.process(self.mestate.flightmode_selections, self.mestate.mlog._flightmodes)
+        lenmavlist = len(mh.mav_list)
+        mh.mav_list = []
+        child = multiproc.Process(target=mh.show, args=[lenmavlist], kwargs={'xlim_pipe': self.xlim_pipe})
+        child.start()
+        self.xlim_pipe[1].close()
+        self.mestate.mlog.rewind()
+
+    def check_xlim_change(self):
+        '''histogram never drives xlim changes in other graphs'''
+        return None
+
+    def set_xlim(self, xlim):
+        '''forward a time-range update to the histogram child process'''
+        if self.xlim_pipe is not None and self.xlim != xlim:
+            try:
+                self.xlim_pipe[0].send(xlim)
+            except IOError:
+                return False
+            self.xlim = xlim
+        return True

MAVProxy/modules/lib/grapher.py

@@ -17,6 +17,7 @@
 from math import *
 from pymavlink.mavextra import *
 import matplotlib.pyplot as plt
+import matplotlib.ticker
 from pymavlink import mavutil
 import threading
 import numpy as np
@@ -798,6 +799,129 @@ def show(self, lenmavlist, block=True, xlim_pipe=None, output=None):
         else:
             plt.savefig(output, bbox_inches='tight', dpi=200)
 
+
+class MavHistogram(MavGraph):
+    '''Histogram of a single log data field with live time-range filtering.'''
+
+    def __init__(self, flightmode_colourmap=None):
+        super().__init__(flightmode_colourmap)
+        self.bins = 50
+        self.show_stats = True
+        self._all_x = None
+        self._all_y = None
+
+    def set_bins(self, bins):
+        '''set number of histogram bins'''
+        self.bins = bins
+
+    def set_show_stats(self, show_stats):
+        '''set whether to overlay median and std dev lines'''
+        self.show_stats = show_stats
+
+    def _draw_histogram(self, y_data):
+        '''redraw histogram axes with the supplied data'''
+        self.ax1.cla()
+        label = self.fields[0] if self.fields else ''
+        title = self.title if self.title else 'Histogram: ' + label
+        self.ax1.set_title(title)
+        self.ax1.hist(y_data, bins=self.bins, color=colors[0], alpha=0.7, label=label,
+                      weights=np.ones(len(y_data)) / len(y_data) * 100.0)
+        self.ax1.set_xlabel(label)
+        self.ax1.set_ylabel('Frequency (%)')
+        self.ax1.yaxis.set_major_formatter(matplotlib.ticker.FormatStrFormatter('%.1f%%'))
+        self.ax1.xaxis.set_major_locator(matplotlib.ticker.MaxNLocator(nbins=15))
+        self.ax1.xaxis.set_minor_locator(matplotlib.ticker.AutoMinorLocator())
+        self.ax1.tick_params(axis='x', which='major', labelrotation=45)
+
+        if self.show_stats and len(y_data) > 0:
+            median = np.median(y_data)
+            mean   = np.mean(y_data)
+            std    = np.std(y_data)
+
+            stat_styles = [
+                (median, 'black',  '-',  2.0, 'Median %.3g' % median),
+                (mean - std,   'orange', '--', 1.5, u'\u00b11\u03c3 (%.3g)' % std),
+                (mean + std,   'orange', '--', 1.5, None),
+                (mean - 2*std, 'red',    ':',  1.5, u'\u00b12\u03c3 (%.3g)' % (2*std)),
+                (mean + 2*std, 'red',    ':',  1.5, None),
+                (mean - 3*std, 'purple', '-.',  1.2, u'\u00b13\u03c3 (%.3g)' % (3*std)),
+                (mean + 3*std, 'purple', '-.',  1.2, None),
+            ]
+            for (xval, col, ls, lw, lbl) in stat_styles:
+                self.ax1.axvline(x=xval, color=col, linestyle=ls,
+                                 linewidth=lw, label=lbl)
+
+        self.ax1.legend(loc=self.legend)
+        self.fig.tight_layout()
+        self.fig.canvas.draw_idle()
+
+    def _hist_xlim_timer(self):
+        '''called every 100 ms to check for time-range updates from other graphs'''
+        if self.closing or self.xlim_pipe is None:
+            return
+        try:
+            if not self.xlim_pipe[1].poll():
+                return
+            xlim = self.xlim_pipe[1].recv()
+        except Exception:
+            return
+        if xlim == self.xlim or xlim is None:
+            return
+        self.xlim = xlim
+        mask = (self._all_x >= xlim[0]) & (self._all_x <= xlim[1])
+        y_filtered = self._all_y[mask]
+        if len(y_filtered) == 0:
+            return
+        self._draw_histogram(y_filtered)
+
+    def show(self, lenmavlist, block=True, xlim_pipe=None, output=None):
+        '''show histogram plot in a new figure'''
+        if xlim_pipe is not None:
+            xlim_pipe[0].close()
+        self.xlim_pipe = xlim_pipe
+
+        if not self.x or len(self.x[0]) == 0:
+            print("No data for histogram")
+            return
+
+        self._all_x = np.array(self.x[0])
+        self._all_y = np.array(self.y[0])
+
+        label = self.fields[0] if self.fields else ''
+        title = self.title if self.title else 'Histogram: ' + label
+
+        interactive = output is None
+        if interactive:
+            plt.ion()
+
+        self.fig, ax = plt.subplots(figsize=(10, 6))
+        self.ax1 = ax
+
+        self._draw_histogram(self._all_y)
+
+        self.fig.canvas.get_default_filename = lambda: ''.join(
+            'histogram' if self.title is None else
+            (c if c.isalnum() else '_' for c in title)) + '.png'
+        if self.fig.canvas.manager is not None:
+            self.fig.canvas.manager.set_window_title(title)
+        self.fig.canvas.mpl_connect('close_event', self.close_event)
+
+        if output is None:
+            if xlim_pipe is not None:
+                self.xlim_t = self.fig.canvas.new_timer(interval=100)
+                self.xlim_t.add_callback(self._hist_xlim_timer)
+                self.xlim_t.start()
+            plt.draw()
+            plt.show(block=block)
+        elif output.endswith('.html'):
+            import mpld3
+            html = mpld3.fig_to_html(self.fig)
+            with open(output, 'w') as f_out:
+                f_out.write(html)
+        else:
+            plt.savefig(output, bbox_inches='tight', dpi=200)
+
+
 if __name__ == "__main__":
     from argparse import ArgumentParser
     parser = ArgumentParser(description=__doc__)

MAVProxy/tools/MAVExplorer.py

@@ -112,6 +112,8 @@ def __init__(self):
               MPSetting('sync_xmap', bool, True, 'sync X-axis zoom for map'),
               MPSetting('legend', str, 'upper left', 'legend position'),
               MPSetting('legend2', str, 'upper right', 'legend2 position'),
+              MPSetting('hist_bins', int, 50, 'histogram bin count', tab='Graph'),
+              MPSetting('hist_show_stats', bool, True, 'show median/std dev on histogram', tab='Graph'),
               MPSetting('axis_mode', str, 'auto', 'y-axis layout mode',
                         choice=['auto', 'dual', 'multi']),
               MPSetting('title', str, None, 'Graph title'),
@@ -131,6 +133,7 @@ def __init__(self):
             "condition" : ["(VARIABLE)"],
             "graph"     : ['(VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE)'],
             "graphs"    : ['(PREDEFINED_GRAPH)'],
+            "histogram" : ['(VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE)', '--bins (VARIABLE) (VARIABLE)'],
             "dump"      : ['(MESSAGETYPE)', '--verbose (MESSAGETYPE)'],
             "map"       : ['(VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE) (VARIABLE)'],
             "param"     : ['download', 'check', 'help (PARAMETER)', 'save', 'savechanged', 'diff', 'show', 'check'],
@@ -260,6 +263,7 @@ def setup_menus():
                               items=[MPMenuItem('MagFit', 'MagFit', '# magfit'),
                                      MPMenuItem('Stats', 'Stats', '# stats'),
                                      MPMenuItem('FFT', 'FFT', '# fft'),
+                                     MPMenuItem('Histogram', 'Histogram', '# histogram'),
                                      MPMenuItem('Location Analysis', 'Location', '# locationAnalysis')]))
 
     mestate.console.set_menu(TopMenu, menu_callback)
@@ -579,6 +583,48 @@ def cmd_graph(args):
         #print("initial: ", xlimits.last_xlim)
         grui[-1].set_xlim(xlimits.last_xlim)
 
+def cmd_histogram(args):
+    '''plot histogram of a single log data field'''
+    usage = "usage: histogram [--bins N] <FIELD>"
+    if len(args) < 1:
+        print(usage)
+        return
+
+    bins = mestate.settings.hist_bins
+    fields = []
+    i = 0
+    while i < len(args):
+        if args[i] == '--bins':
+            if i + 1 < len(args):
+                try:
+                    bins = int(args[i+1])
+                    i += 2
+                    continue
+                except ValueError:
+                    print("Invalid bins value: %s" % args[i+1])
+                    return
+        fields.append(args[i])
+        i += 1
+
+    if not fields:
+        print(usage)
+        return
+    if len(fields) > 1:
+        print("histogram only accepts one field at a time (got: %s)" % ', '.join(fields))
+        return
+
+    check_vehicle_type()
+    from MAVProxy.modules.lib.graph_ui import Histogram_UI
+    expression = fields[0]
+    graphdef = GraphDefinition(mestate.settings.title, expression, '', [expression], None)
+    hui = Histogram_UI(mestate)
+    hui.display_histogram(graphdef, bins=bins, show_stats=mestate.settings.hist_show_stats)
+    grui.append(hui)
+    global xlimits
+    if xlimits.last_xlim is not None and mestate.settings.sync_xzoom:
+        grui[-1].set_xlim(xlimits.last_xlim)
+
+
 def cmd_graphs(args):
     '''graphs command'''
     usage = "usage: graphs <PREDEFINED_GRAPH_NAME>"
@@ -1743,6 +1789,7 @@ def main_loop():
 command_map = {
     'graph'      : (cmd_graph,     'display a graph'),
     'graphs'     : (cmd_graphs,    'display a predefined graph'),
+    'histogram'  : (cmd_histogram, 'plot histogram of log data fields'),
     'set'        : (cmd_set,       'control settings'),
     'reload'     : (cmd_reload,    'reload graphs'),
     'save'       : (cmd_save,      'save a graph'),