#!/usr/bin/env?python
“““
Tool?to?convert?from?logfile?of?GPS-measurements?to?RINEX?format
“““
import?argparse
import?datetime
import?math
import?sys

#?Define?constants
SPEED_OF_LIGHT?=?299792458.0;?#?[m/s]
GPS_L1_FREQ?=?154.0?*?10.23e6
GPS_L1_WAVELENGTH?=?SPEED_OF_LIGHT?/?GPS_L1_FREQ
GPS_WEEKSECS?=?604800?#?Number?of?seconds?in?a?week
NS_TO_S?=?1.0e-9
NS_TO_M?=?NS_TO_S?*?SPEED_OF_LIGHT??#?Constant?to?transform?from?nanoseconds?to?meters

#?Origin?of?the?GPS?time?scale
GPSTIME?=?datetime.datetime（1980?1?6）

#?Flags?to?check?wether?the?measurement?is?correct?or?not
#?https://developer.android.com/reference/android/location/GnssMeasurement.html#getState（）
STATE_CODE_LOCK?=?int（0x00000001）
STATE_TOW_DECODED?=?int（0x00000008）

#?Constellation?types
CONSTELLATION_GPS?=?1
CONSTELLATION_SBAS?=?2
CONSTELLATION_GLONASS?=?3
CONSTELLATION_QZSS?=?4
CONSTELLATION_BEIDOU?=?5
CONSTELLATION_UNKNOWN?=?0

def?get_raw_field_descr_from_header（file_handler）:
????“““
????Get?the?raw?field?descriptors?of?the?GNSS?Logger?log.?These?field?descriptors
????will?be?later?used?to?identify?the?data.

????This?method?advances?the?file?pointer?past?the?line?where?the?raw?fields
????are?described
????“““

????for?line?in?file_handler:

????????#?Check?if?the?line?is?the?line?containing?the?field?descriptors?of?the
????????#?“Raw“?lines
????????if?line.startswith（“#?Raw“）:

????????????return?[f.strip（）?for?f?in?line[2:].strip（）.split（‘‘）[1:]]


def?check_state（state）:
????“““
????Checks?if?measurement?is?valid?or?not?based?on?the?Sync?bits
????“““

????if?（state?&?STATE_CODE_LOCK）?==?0:
????????raise?Exception（“State?[?0x{0:2x}?{0:8b}?]?has?STATE_CODE_LOCK?[?0x{1:2x}?{1:8b}?]?not?valid“.format（state?STATE_CODE_LOCK））

????if?（state?&?STATE_TOW_DECODED）?==?0:
????????raise?Exception（“State?[?0x{0:2x}?{0:8b}?]?has?STATE_TOW_DECODED?[?0x{1:2x}?{1:8b}?]?not?valid“.format（state?STATE_TOW_DECODED））

????return?True


def?check_rinex_field（name?value?size）:
????“““
????Checks?if?the?field?is?of?proper?length?and?if?not?it?issues?a?
????warning?message?and?returns?a?sanitized?（cropeed）?version?of?the?
????field
????“““

????if?value?is?None:
????????return?“UNKN“

????if?（len（value）?>?size）:
????????sys.stderr.write（“The?‘{0}‘?field?[?{1}?]?is?too?long?[?{2}?].?Cropping?to?{3}?characters\n“.format（name?value?len（value）?size））
????????
????????return?value[0:size]

????return?value


def?rinex_header（runby=None?marker=None?observer=None?agency=None
?????????????????receiver=None?rxtype=None?version=‘Android?OS?>7.0‘
?????????????????antenna=None?anttype=‘internal‘
?????????????????approx_position=[000]?antenna_hen=[0.0?0.0?0.0]）:
????“““
????Print?RINEX?header?as?a?string

????The?fields?are?the?ones?specified?in?the?RINEX?format?definition?that?can
????be?found?at:
????https://igscb.jpl.nasa.gov/igscb/data/format/rinex211.txt
????“““


????VERSION?=?2.11
????TYPE?=?‘OBSERVATION?DATA‘
????SATSYS?=?‘M?（MIXED）‘

????#?Version?line
????h?=?“{0:9.2f}???????????{1:<

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2017-08-29?06:36??android_rinex-master\
?????文件????????1312??2017-08-29?06:36??android_rinex-master\LICENSE
?????文件????????2452??2017-08-29?06:36??android_rinex-master\README.md
?????文件???????17224??2017-08-29?06:36??android_rinex-master\android_to_rinex.py
?????目錄???????????0??2017-08-29?06:36??android_rinex-master\data\
?????文件?????5373110??2017-08-29?06:36??android_rinex-master\data\pseudoranges_log_2017_07_17_13_46_25.txt