if loop repeating first if statement

Question

I'm trying to create a continuous question loop to process all my calculations for my nmea sentences in my project. For some reason only the first if statement is executed. What am I doing wrong? I'm still fairly new to python

   if command_type == "$GPGGA" or "GPGGA" or "GGA":
        #define the classes
        gps = GPS()
        createworkbook = CreateWorkbook()
        convertfile = ConvertFile()
        print_gps = PrintGPS()
        #do the deeds
        createworkbook.openworkbook(data)
        print_gps.process_gpgga_data(data)
        createworkbook.closeworkbook_gpgga(data) 
        convertfile.convert2csv(data)
        convertfile.convert2kml(data)
    if command_type == "$GPRMC" or "GPRMC" or "RMC":
        #define the classes
        gps = GPS()
        createworkbook = CreateWorkbook()
        convertfile = ConvertFile()
        print_gps = PrintGPS()
        #do the deeds
        createworkbook.openworkbook(data)
        print_gps.process_gprmc_data(data)
        createworkbook.closeworkbook_gprmc(data) 
        convertfile.convert2csv(data)
        convertfile.convert2kml(data)
    if command_type == "$GPGLL" or "GPGLL" or "GLL":
        #define the classes
        gps = GPS()
        createworkbook = CreateWorkbook()
        convertfile = ConvertFile()
        print_gps = PrintGPS()
        #do the deeds
        createworkbook.openworkbook(data)
        print_gps.process_gpgll_data(data)
        createworkbook.closeworkbook_gpgll(data) 
        convertfile.convert2csv(data)
        convertfile.convert2kml(data)
    if command_type == "$GPGSA" or "GPGSA" or "GSA":
        #define the classes
        gps = GPS()
        createworkbook = CreateWorkbook()
        convertfile = ConvertFile()
        print_gps = PrintGPS()
        #do the deeds
        createworkbook.openworkbook(data)
        print_gps.process_gpgsa_data(data)
        createworkbook.closeworkbook_gpgsa(data) 
        convertfile.convert2csv(data)  
    if command_type == "$GPVTG" or "GPVTG" or "VTG":
        print('Better check $GPRMC')
    else:
        print("Invalid type:", command_type)

    list_gps_commands(data)     
    wannalook = input('Want to look at another message or no?')
    if not wannalook.startswith('y'):
        keep_asking = False
        print('********************')
        print('**mischief managed**')
        print('********************')

also change those 'ifs' with 'elifs', you want to enter the 'else' in the end only if none fo the above are true, right? — tglaria, Jan 05 '16 at 13:07

dot.Py · Accepted Answer · 2016-01-05T13:01:51.473

2

Instead of:

 if command_type == "$GPGGA" or "GPGGA" or "GGA":

use:

  if command_type == "$GPGGA" or command_type == "GPGGA" or command_type == "GGA":

or:

if command_type in ["$GPGGA", "GPGGA", "GGA"]:

edited Jan 05 '16 at 13:01

answered Jan 05 '16 at 12:55

dot.Py

5,007
5
31
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1

Better to use the `in` operator, is cleaner – César Jan 05 '16 at 12:57
1

Like `if command_type in ["$GPGGA", "GPGGA", "GGA"]:` ? – dot.Py Jan 05 '16 at 12:58
1

Yup, just an opinion. And also you should explain why his solution was evaluating to true because of the truth value of a non-empty string – César Jan 05 '16 at 13:00
the 'in' operator worked! thanks guys! – Daniel Jan 05 '16 at 13:10
Maybe explain why the "in" solution works ? :) – Anthony Granger Jan 05 '16 at 13:15
if command_type in ('$GPGGA', 'GPGGA', 'GGA','$gpgga', 'gpgga', 'gga'): – Daniel Jan 05 '16 at 13:26
I've never used the 'in' operator this way but somehow it allows me to switch from one message type to the next when prompted. – Daniel Jan 05 '16 at 13:28

score 2 · Answer 2 · answered Jan 05 '16 at 12:57

2

if command_type == "$GPGGA" or "GPGGA" or "GGA":

As you can see, here you are not trying to check if command_type is valued "$GPGGA" or "GPGGA" or "GGA". But if command_type == "$GPGGA" is true or "GPGGA" is true or "GGA" is true.

And a non-empty string in python is always true : your first condition will be evaluated true.

So you have to do :

if command_type == "$GPGGA" or command_type == "GPGGA" or command_type == "GGA"

answered Jan 05 '16 at 12:57

Anthony Granger

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23

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or just `if command_type in ("$GPGGA", "GPGGA", "GGA"):` – Duncan Jan 05 '16 at 13:20
You are right (not with "()" but "[]"). But I just wanted to clarify why the first condition is true. – Anthony Granger Jan 05 '16 at 13:21
what's your objection to my parentheses? Either a tuple or a list works fine here but it is probably more usual to use a tuple. – Duncan Jan 05 '16 at 13:23
Oh yes sorry, my bad. I'm used to list in this scenario :) – Anthony Granger Jan 05 '16 at 13:28

if loop repeating first if statement

2 Answers2