我是python新手，正在尝试编写一个简单的脚本来从GPX文件中提取特定的信息。下面我的脚本中的限制性问题是，它似乎无法在else语句中找到dtime，但可以在第一个if语句中看到它。也许我对python的陌生感正渐渐消失，因为我确信有一个简单的解决方案。有谁能告诉我如何让它看到变量dtime或者我做错了什么？在

此外，有没有更好的方法让它使用标志。D和-P永远不会有用户输入，但目的是在定义这两个标志时读取GPX文件。在

以下是脚本：#!/usr/bin/env pnpython3

import gpxpy.parser

import os

def get_args () :

''' Parse input args

-x gpx filename

-d default deploy time yyyy:jjj:hh:mm:ss.sss

-p default pickup time yyyy:jjj:hh:mm:ss.sss

-D read deploy time from GPX file

-P read pickup time from GPX file

-l line number (array)

'''

global GPX, DEPLOY, PICKUP, LINE

from optparse import OptionParser

oparser = OptionParser ()

oparser.usage = "munge_wp.py -x gps_file_name -d deploy_yyyy:jjj:hh:mm:ss.sss -ppickup_yyyy:jjj:hh:mm:ss.sss -l line_number"

oparser.description = "Read a GPX way point file and produce a CSV file."

oparser.add_option ("-x", "--gpx", dest = "gpx_file",help = "GPX input file",metavar = "gpx_file")

oparser.add_option ("-d", "--deploy", dest = "deploy_time",help="Deploy time yyyy:jjj:hh:mm:ss.sss",metavar = "deploy_time")

oparser.add_option ("-p", "--pickup", dest = "pickup_time",

help="Pickup time yyyy:jjj:hh:mm:ss.sss",

metavar = "pickup_time")

oparser.add_option ("-D", "--Deploy", dest = "D_time",help="D_time will be read from GPX file and put in the following format yyyy:jjj:hh:mm:ss.sss",metavar = "D_time")

oparser.add_option ("-P", dest = "P_time", help="P_time will be read from GPX file and put

in the following format yyyy:jjj:hh:mm:ss.sss",

metavar = "P_time")

oparser.add_option ("-l", "--line", dest = "line_number",help = "The line number. Caution: Assumes that all stations in GPX file are on same line",metavar = "line_number")

options, args = oparser.parse_args()

#print options.outfile

GPX = options.gpx_file

DEPLOY = options.deploy_time

PICKUP = options.pickup_time

LINE = options.line_number

DTIME = options.D_time

PTIME = options.P_time

def open_gpx () :

fh = open (GPX)

gpx_parser = gpxpy.parser.GPXParser (fh)

gpx_parser.parse ()

fh.close ()

return gpx_parser.get_gpx ()

if __name__ == '__main__' :

get_args ()

gpx = open_gpx ()

print "#STA\tDAS\tLAT\tLON\tELEV\tDEPLOY\tPICKUP\tLINE"

for wp in gpx.waypoints :

s=wp.name

staname = s.split('-')[0]

#print staname

das = s.split('-')[1]

#print das

t=wp.time

dtme=os.popen("date -d t +%Y:%j:%H:%M:%S")

dtime=dtme.read()

if "DEPLOY" in locals() or "PICKUP" in locals():

line = "{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{6}\t{7}".format (staname,

das,

wp.latitude,

wp.longitude,

wp.elevation,

DEPLOY,

PICKUP,

LINE)

print line

else:

line = "{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{6}\t{7}".format (staname,

das,

wp.latitude,

wp.longitude,

wp.elevation,

dtime,

dtime,

LINE)

print line