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Getting position data from UBX protocol

I am working on a project which is use ublox .ubx protocol to getting position information. I'm using serial communication to connect my GPS module and getting position information to python sketch. I used Serial and pyubx2 libraries my sketch as follows,
from serial import Serial
from pyubx2 import UBXReader
stream = Serial('COM8', 38400)
while True:
ubr = UBXReader(stream)
(raw_data, parsed_data) = ubr.read()
print(parsed_data)
Then I have received information from GPS module as follows. It is continuously sending many of information in every second like as follows,
<UBX(NAV-SOL, iTOW=00:11:43, fTOW=-215069, week=0, gpsFix=0, gpsfixOK=0, diffSoln=0, wknSet=0, towSet=0, ecefX=637813700, ecefY=0, ecefZ=0, pAcc=649523840, ecefVX=0, ecefVY=0, ecefVZ=0, sAcc=2000, pDOP=99.99, reserved1=2, numSV=0, reserved2=215800)>
<UBX(NAV-PVT, iTOW=00:11:43, year=2015, month=10, day=18, hour=0, min=12, second=1, validDate=0, validTime=0, fullyResolved=0, validMag=0, tAcc=4294967295, nano=-215068, fixType=0, gnssFixOk=0, difSoln=0, psmState=0, headVehValid=0, carrSoln=0, confirmedAvai=0, confirmedDate=0, confirmedTime=0, numSV=0, lon=0.0, lat=0.0, height=0, hMSL=-17000, hAcc=4294967295, vAcc=3750027776, velN=0, velE=0, velD=0, gSpeed=0, headMot=0.0, sAcc=20000, headAcc=180.0, pDOP=99.99, invalidLlh=0, lastCorrectionAge=0, reserved0=2312952, headVeh=0.0, magDec=0.0, magAcc=0.0)>
I want to assign those position information (latitude, longitude, altitude etc.) into variables and hope to do some analysis part in further. So how can I derive positional information individually from this type of sentences.

Try something like this (press CTRL-C to terminate) ...
from serial import Serial
from pyubx2 import UBXReader
try:
stream = Serial('COM8', 38400)
while True:
ubr = UBXReader(stream)
(raw_data, parsed_data) = ubr.read()
# print(parsed_data)
if parsed_data.identity == "NAV-PVT":
lat, lon, alt = parsed_data.lat, parsed_data.lon, parsed_data.hMSL
print(f"lat = {lat}, lon = {lon}, alt = {alt/1000} m")
except KeyboardInterrupt:
print("Terminated by user")
For further assistance, refer to https://github.com/semuconsulting/pyubx2 (there are several example Python scripts in the /examples folder).

How to receive multiple ATCommand response packets from the local xbee for the "FN" (finding neighbour) AT command using python digi-xbee library

This is the code which works well for all AT commands except "FN":
from digi.xbee.devices import XBeeDevice
#Initialise a serial port for the local xbee
local_xbee = XBeeDevice("/dev/tty.usbserial-AH02D9Q4", 9600).
#Opens serial port for sending commands
local_xbee.open()
#Sets new timeout for sync command operation
local.set_sync_ops_timeout(10).
#Send "FN" AT command to local xbee to receive neighbour list
neighbour_xbee_list = local.get_parameter("FN")
print(neighbour_xbee_list)
local_xbee.close()
Note:
The above code returns only one neighbour whereas I have more than one nodes in the network.

I believe the point of the question is not how to use the FN command, but how to discover neighbors.
For this, you can use the start_discovery_process function described here.
http://xbplib.readthedocs.io/en/latest/user_doc/discovering_the_xbee_network.html#discovernetwork

import serial
from digi.xbee.packets.common import ATCommPacket
from digi.xbee.devices import XBeeDevice
from digi.xbee.reader import PacketListener
from digi.xbee.serial import XBeeSerialPort
from digi.xbee.util import utils
import time
local_xbee = XBeeDevice("/dev/tty.usbserial-AH02D9Q4", 9600)
local_xbee.open()
print("This is : ", local_xbee.get_node_id())
print(local_xbee._packet_listener.is_running())
parameter = "FN"
frame_id = 33
my_packet = ATCommPacket(frame_id, parameter)
#print(my_packet)
#print(my_packet.frame_id)
#print(my_packet.command)
final_send = my_packet.output()
local_xbee._serial_port.write(final_send)
print("Finding Neighbours")
while True:
print(".")
Queue = local_xbee._packet_listener.get_queue()
received_packet = Queue.get_by_id(frame_id)
if received_packet != None:
#if received_packet.status == ATCommandStatus.OK:
final = received_packet._get_api_packet_spec_data().__str__()
print(final)
time.sleep(0.5)
local_xbee.close()

Optimize output of a script by varying input parameters

I have a written a script that uses the code below and I would like to optimize rsi_high and rsi_low to get the best sharpe_ratio:
#
import numpy
import talib as ta
global rsi_high, rsi_low
rsi_high = 63
rsi_low = 41
def myTradingSystem(DATE, OPEN, HIGH, LOW, CLOSE, VOL, exposure, equity, settings):
''' This system uses trend following techniques to allocate capital into the desired equities'''
nMarkets = CLOSE.shape[1] # SHAPE OF NUMPY ARRAY
result, rsi_pos = numpy.apply_along_axis(rsicalc, axis=0, arr=CLOSE)
pos = numpy.asarray(rsi_pos, dtype=numpy.float64)
return pos, settings
def rsicalc(num):
# print rsi_high
try:
rsival = ta.RSI(numpy.array(num,dtype='f8'),timeperiod=14)
if rsival[14] > rsi_high: pos_rsi = 1
elif rsival[14] < rsi_low: pos_rsi = -1
else: pos_rsi = 0
except:
rsival = 0
pos_rsi = 0
return rsival, pos_rsi
def mySettings():
''' Define your trading system settings here '''
settings = {}
# Futures Contracts
settings['markets'] = ['CASH','F_AD', 'F_BO', 'F_BP', 'F_C', 'F_CC', 'F_CD',
'F_CL', 'F_CT', 'F_DX', 'F_EC', 'F_ED', 'F_ES', 'F_FC', 'F_FV', 'F_GC',
'F_HG', 'F_HO', 'F_JY', 'F_KC', 'F_LB', 'F_LC', 'F_LN', 'F_MD', 'F_MP',
'F_NG', 'F_NQ', 'F_NR', 'F_O', 'F_OJ', 'F_PA', 'F_PL', 'F_RB', 'F_RU',
'F_S', 'F_SB', 'F_SF', 'F_SI', 'F_SM', 'F_TU', 'F_TY', 'F_US', 'F_W',
'F_XX', 'F_YM']
settings['slippage'] = 0.05
settings['budget'] = 1000000
settings['beginInSample'] = '19900101'
settings['endInSample'] = '19931231'
settings['lookback'] = 504
return settings
# Evaluate trading system defined in current file.
if __name__ == '__main__':
import quantiacsToolbox
results = quantiacsToolbox.runts(__file__, plotEquity=False)
sharpe_ratio = results['stats']['sharpe']
I suspect that using something like scipy minimize function would do the trick, but I am having trouble understanding how to package my script so that it can be in a usable form.
I have tried putting everything in a function and then running all the code through a number of loops, each time incrementing values but there must be a more elegant way of doing this.
Apologies for posting all my code but I thought it would help if the responder wanted to reproduce my setup and for anyone who is new to quantiacs to see a real example who is faced with the same issue.
Thanks for your help in advance!

Python Web application: Refresh values

I use a template of a python script (running on Raspberry Pi) to send sensor data (i2c) via WiFi to my PC. The problem is, the values are not static. If I start the Web application, it reads the data from the sensor only once. So, if I check the values from my PC, I can see it sent the data correctly, but they won't change.
How can I modify the script to refresh the i2c_output value, without starting the script over and over again?
Here is what I have tried so far:
import web
import sys, os
import smbus
import math
#
# Lot of initialisation... forget that part
#
accel_xout = read_word_2c(0x3b)
accel_yout = read_word_2c(0x3d)
accel_zout = read_word_2c(0x3f)
afs_sel = read_word_2c(0x28)
LSB_afs_sel = 16384.0
accel_xout_sc = accel_xout / LSB_afs_sel
accel_yout_sc = accel_yout / LSB_afs_sel
accel_zout_sc = accel_zout / LSB_afs_sel
i2c_output = str(accel_xout_sc) + str(accel_yout_sc) + str(accel_zout_sc)
urls = ( '/','Index',
)
class Index:
def GET(self):
return i2c_output
if __name__=="__main__":
app=web.application(urls,globals())
app.run()

Move the code that retrieves the sensor data into a method and invoke that method each time the index is called.
def get_sensor_output():
#
# Lot of initialisation... forget that part
#
accel_xout = read_word_2c(0x3b)
accel_yout = read_word_2c(0x3d)
accel_zout = read_word_2c(0x3f)
afs_sel = read_word_2c(0x28)
LSB_afs_sel = 16384.0
accel_xout_sc = accel_xout / LSB_afs_sel
accel_yout_sc = accel_yout / LSB_afs_sel
accel_zout_sc = accel_zout / LSB_afs_sel
i2c_output = str(accel_xout_sc) + str(accel_yout_sc) + str(accel_zout_sc)
return i2c_output
class Index:
def GET(self):
return get_sensor_output()
Note: You may want to implement some sort of cache depending on how often this get method is called. currently each call will retrieve the sensor data, which may or may not be an expensive operation that will drain the battery on your pi

Dpkt lib - how to add timestamp to packet

So I am trying to create my own pcap file, I've created a msg using dpkt but I am not understanding how to maneuver timestamp, from what I've seen it is the 3rd parameter in writepkt but I don't understand how to initial the variable.. this is a part of my code
output_pcapfile = dpkt.pcap.Writer(open(__file__+'.pcap','wb'))
tcpSrc.data = 'Some data\r\n'
ipSrc.data = tcpSrc
ipSrc.len = len(str(ipSrc))
ethSrc.data = ipSrc
packet_count = 1
output_pcapfile.writepkt(ethSrc,packet_count) # somehow get timestamp for third parameter!!
Anyone has an idea? thanks !

looking at the 1.7 source for pcap.py,
I see:
def writepkt(self, pkt, ts=None):
if ts is None:
ts = time.time()
#some more code..
This function takes two non-self arguments
The timestamp will be created if you only pass in the pkt itself, e.g.
output_pcapfile.writepkt(ethSrc)