Get nearest xbee beacon (visualization in NodeBox)

nearest_xbee.py

import csv
from collections import Counter
speed(60)
width = 400
size(width, width)
SAMPLE = True


class RingBuffer(object):
    """                                                                                                                                                                                        
    See: http://www.saltycrane.com/blog/2007/11/python-circular-buffer/                                                                                                                        
    """
    def __init__(self, buf_size=8, boundary_size=1, default=None):
        self.buf = [default] * buf_size
        self.buf_size = buf_size
        self.boundary_size = boundary_size

    def append(self, value):
        self.buf.pop(0)
        self.buf.append(value)

    def get(self):
        return self.buf

    def most_appeared(self):
        ct = Counter()
        for val in self.buf:
            ct[val] += 1
        ct = filter(lambda p: p[0] != None, sorted(ct.items(), key=lambda tpl: -tpl[1]))
        if len(ct):
            return ct[0][0]


rssi_list = []
rssi_doc = csv.reader(open('out.csv'))
for row in rssi_doc:
    rssi_list.append(row)
font("Helvetica", 20)

def setup():
    global count
    global xbees
    global samples
    count = 0
    xbees = {}
    samples = RingBuffer(buf_size=25)

Y = 256
xbee_ids = ('0x1007', '0x1002', '0x1004', '0x1009')
def draw_rssi(addr, rssi, is_max=False):
    index = xbee_ids.index(addr)
    x = index * 100 + 30
    if is_max:
        fill(0.3, 0.8, 0.3)
    else:
        fill(0.5, 0.5, 0.5)
    rect(x, Y + rssi * 2, 30, -rssi * 2)
    font("Helvetica", 12)
    text("%s\n%ddBm" % (addr, rssi), x - 10, Y + 16)

def draw_count(count, time):
    fill(0.7)
    text("%04d/%04d\n%s" % (count + 1, len(rssi_list), time), 200, Y + 64)

def draw():
    global count
    global xbees
    global samples
    if count > len(rssi_list) - 1:
        count = len(rssi_list) - 1
    created_at, xbee_id, rssi = rssi_list[count]
    rssi = int(rssi)
    xbees[xbee_id] = rssi
    max_xbee_id = sorted(xbees.items(), key=lambda tpl: -tpl[1])[0][0]
    samples.append(max_xbee_id)
    for addr, rssi in xbees.iteritems():
        draw_rssi(addr, rssi, addr==samples.most_appeared())
    draw_count(count, created_at[:-6])

    # axis
    stroke(0.2)
    strokewidth(2)
    line(10, Y, width - 10, Y)

    count += 1

out.csv