I am a beginner in programming, I am using the example
import argparse
import pandas as pd
def read_data(fname):
return pd.read_csv(fname)
if __name__ == "__main__":
options = argparse.ArgumentParser()
options.add_argument("-f", "--file", type=str, required=True)
args = options.parse_args()
data = read_data(args.file)
print(data)
I got this error:
error: the following arguments are required: -f/--file
Would you please help me how can define my file name, where to write it?
Thank you
With required=True, the command-line must include the -f or --file arguments:
# python myprog.py --file=somefile.txt
Make required=False
options.add_argument("-f", "--file", type=str, required=False)
Your original code would require yourprogram -f filename.csv where yourprogram is the name of your script file, and filename.csv is the name of a CSV file with input data. The -f option can also be spelled out in longhand as --file.
But options should typically be optional. Make this a regular required argument if it is mandatory.
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser.add_argument("file", type=str)
args = parser.parse_args()
data = read_data(args.file)
print(data)
Usage: yourprogram filename.csv
Perhaps you are using python yourprogram.py to run this script; then the usage would be python yourprogram.py filename.csv
Related
I have a python script that requires the user to enter two arguments to run it, the arguments could be named anything.
I have also used argparse to allow the users to use a switch '-h' to get instructions of what is required to run the script.
The problem is that now I have used argparse I am getting an error when I pass my two randomly named arguments with the script.
import argparse
parser = argparse.ArgumentParser(add_help=False)
parser.add_argument('-h', '--help', action='help',
help='To run this script please provide two arguments')
parser.parse_args()
currently when I run python test.py arg1 arg2 the error is
error: unrecognized arguments: arg1 arg2
I would like the code to allow the user to run test.py with a -h if required to see the instructions but also allow them to run the script with any two arguments as well.
Resolution with help tag to provide the user with context regarding the arguments required.
parser = argparse.ArgumentParser(add_help=False)
parser.add_argument('-h', '--help', action='help', help='To run this script please provide two arguments: first argument should be your scorm package name, second argument should be your html file name. Note: Any current zipped folder in the run directory with the same scorm package name will be overwritten.')
parser.add_argument('package_name', action="store", help='Please provide your scorm package name as the first argument')
parser.add_argument('html_file_name', action="store", help='Please provide your html file name as the second argument')
parser.parse_args()
Try the following code :-
import argparse
parser = argparse.ArgumentParser(add_help=False)
parser.add_argument('-h', '--help', action='help',
help='To run this script please provide two arguments')
parser.add_argument('arg1')
parser.add_argument('arg2')
args, unknown = parser.parse_known_args()
All your unknown arguments will be parsed in unknown and all known in args.
import argparse
parser = argparse.ArgumentParser(description='sample')
# Add mandatory arguments
parser.add_argument('arg1', action="store")
parser.add_argument('arg2', action="store")
# Parse the arguments
args = parser.parse_args()
# sample usage of args
print (float(args.arg1) + float(args.arg2))
You need to add those arguments to the parser:
parser.add_argument("--arg1", "-a1", dest='arg1', type=str)
parser.add_argument("--arg2","-a2", dest='arg2', type=str)
If those arguments don't have the param required=true, you will be able to call the program without this arguments, so you can run the program with only the -h flag. To run the program with the arguments:
python test.py --arg1 "Argument" --arg2 "Argument"
Then, to have the arguments in variables you have to read them:
args = parser.parse_args()
argument1=args.arg1
argument2=args.arg2
I am in the bit of a weird situation where I need a Python function to run from within a script, with the script then called from my main code.
I wanted to use the subprocess module, and know how to use it to pass arguments to a pure script, but the thing is, I need to pass the arguments to the nested Python function within, most of which are optional and have default values.
I thought arparse would help me do this somehow.
Here is an example of what I am trying:
## Some Argparse, which will hopefully help
import argparse
parser = argparse.ArgumentParser()
## All arguments, with only "follow" being required
parser.add_argument('file_name', help='Name of resulting csv file')
parser.add_argument('sub_name', help='Sub-name of resulting csv file')
parser.add_argument('follow', help='Account(s) to follow', required=True)
parser.add_argument('locations', help='Locations')
parser.add_argument('languages', help='Languages')
parser.add_argument('time_limit', help='How long to keep stream open')
args = parser.parse_args()
## Actual Function
def twitter_stream_listener(file_name=None,
sub_name='stream_',
auth = api.auth,
filter_track=None,
follow=None,
locations=None,
languages=None,
time_limit=20):
... function code ...
... more function code ...
...
...
## End of script
If you are passing arguments to functions all you need to do is feed them into the function when you're executing them:
import argparse
parser = argparse.ArgumentParser()
parser.add_argument("-o", "--output_file_name", help="Name of resulting csv file")
parser.add_argument("-s", "--sub_name", default="stream_", help="Sub-name of resulting csv file")
parser.add_argument("-f", "--follow", help="Account(s) to follow", required=True)
parser.add_argument("-loc", "--locations", default=None, help="Locations")
parser.add_argument("-lan", "--languages", default=None, help="Languages")
parser.add_argument("-t", "--time_limit", default=20, help="How long to keep stream open")
options = parser.parse_args()
# then just pass in the arguments when you run the function
twitter_stream_listener(file_name=options.output_file_name,
sub_name=options.sub_name,
auth=api.auth,
filter_track=None,
follow=options.follow,
locations=options.locations,
languages=options.languages,
time_limit=options.time_limit)
# or, pass the arguments into the functions when defining your function
def twitter_stream_listener_with_args(file_name=options.output_file_name,
sub_name=options.sub_name,
auth=api.auth,
filter_track=None,
follow=options.follow,
locations=options.locations,
languages=options.languages,
time_limit=options.time_limit):
# does something
pass
# then run with default parameters
twitter_stream_listener_with_args()
You can specify defaults in the argparse section (if that is what you are trying to achieve):
#!/usr/bin/python
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--argument', default = 'something', type = str, help = 'not helpful')
parser.add_argument('--arg2', default = None, type = str, help = 'not helpful')
args = parser.parse_args()
def foo(arg , arg2 ):
print(arg)
if not arg2 is None:
print(arg2)
foo(args.argument, args.arg2)
Then calling:
$ ./test.py
something
$ ./test.py --argument='somethingelse'
somethingelse
$ ./test.py --arg2=123
something
123
$ ./test.py --arg2='ipsum' --argument='lorem'
lorem
ipsum
Is this helpful?
You can do it like that:
import argparse
## Actual Function
def twitter_stream_listener(file_name=None,
sub_name='stream_',
auth=api.auth,
filter_track=None,
follow=None,
locations=None,
languages=None,
time_limit=20):
# Your content here
if __name__ == '__main__':
parser = argparse.ArgumentParser()
## All arguments, with only "follow" being required
parser.add_argument('follow', help='Account(s) to follow')
parser.add_argument('--file_name', help='Name of resulting csv file')
parser.add_argument('--sub_name', help='Sub-name of resulting csv file')
parser.add_argument('--locations', help='Locations')
parser.add_argument('--languages', help='Languages')
parser.add_argument('--time_limit', help='How long to keep stream open')
args = parser.parse_args()
twitter_stream_listener(file_name=args.file_name, sub_name=args.sub_name, follow=args.follow,
locations=args.locations, languages=args.languages, time_limit=args.time_limit)
follow will be the only required argument and the rest optional. Optional ones have to be provided with -- at the beginning. You can easily use the module with subprocess if you need it.
Example call using command line:
python -m your_module_name follow_val --file_name sth1 --locations sth2
I am using argparse to parse the Python command line which is supposed to look like this:
python script_name.py --sdks=first, second
My script looks like this:
sdk_choises = ['aio','sw']
parser = argparse.ArgumentParser(description='Blah blah')
parser.add_argument('--sdks', action='append', nargs='+', required=True, help='specifies target SDK(s)')
args = parser.parse_args()
if 'aio' in args.sdks:
# do something with aio
if 'sw' in args.sdks:
# do something with sw
When I execute:
python script_name.py --sdks=aio, sw I get error:
"usage: script.py [-h] --sdks SDKS [SDKS ...]
build.py: error: unrecognized arguments: sw"
I'd like to be able to choose one or all choices:
python script_name.py --sdks=first
python script_name.py --sdks=second
python script_name.py --sdks=first, second
Where did I go wrong?
The following works nice:
import argparse
parser = argparse.ArgumentParser(description='Blah blah')
parser.add_argument('--sdks', nargs='+', required=True, help='specifies target SDK(s)')
args = parser.parse_args()
print(args.sdks)
You don't need the = when passing options, just use:
$ python test.py --sdks ai pw
['ai', 'pw']
If you prefer your original form of the comma-separated list, plus check if the argument is valid, then I recommend:
parser.add_argument('--sdks', nargs=1, type=lambda s: [sdk_choises[sdk_choises.index(f)] for f in s.split(',')], ...
Even cleaner way is to define it in a separate function similar to lambda above:
parser.add_argument('--sdks', nargs=1, type=my_parse_function, ...
argparse docs has examples for the parsing function with proper error reporting.
With nargs=1 you'd need to remove one extra list layer.
I'm a newbie in python, so please bear with me.
I don't know how to describe,so I'll just show an example.
python CODE.py -i1 input1.txt -i2 input2.txt -o output.txt
Is such thing possible with python? I've looked up for a while but haven't find an answer.
Thank you!
Instead of just linking to the argparse module or the argparse tutorial,
the other respondents probably should have just shown you how to do it:
import argparse
# Build the parser
p = argparse.ArgumentParser(prog='CODE.PY')
p.add_argument('-i1', type=argparse.FileType('r'),
metavar='sourcefile1', help='First input file')
p.add_argument('-i2', type=argparse.FileType('r'),
metavar='sourcefile2', help='Second input file')
p.add_argument('-o', type=argparse.FileType('w'),
metavar='destfile', help='Destination filename')
# Parse sys.argv
ns = p.parse_args()
# Use the files
data1 = ns.i1.read()
data2 = ns.i2.read()
result = data1[:10] + data2[:10]
ns.o.write(result)
A nice feature of argparse is that not only does it build parsers, it creates a nice option for command-line help:
$ python CODE.PY -h
usage: CODE.PY [-h] [-i1 sourcefile1] [-i2 sourcefile2] [-o destfile]
optional arguments:
-h, --help show this help message and exit
-i1 sourcefile1 First input file
-i2 sourcefile2 Second input file
-o destfile Destination filename
Yes, you can use system argument with your code.
Following snippet of code might help you to resolve your problem
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('inFile', nargs=2, help="Choose in file to use")
parser.add_argument('outFile', nargs=1, help="Choose out file to use")
args=parser.parse_args()
your_fun_call( args.inFile , args.outFile[0] )
Might look wierd at first look but you can refer this document
argparse
Note: infile argument has nargs as 2 because you want two input
files ( nargs stands for number of argument)
As thefourtheye said you can used argparse module. But if you want simple solution, just pass 2 inputs and output file paths as arguments to your executable and use sys.argv to get them in your program in order. The sys.argv[0] is your application name, sys.argv[1] is first input file path, sys.argv[2] is second input file path and sys.argv[3] is output file path.
import sys
input1 = sys.argv[1]
input2 = sys.argv[2]
output = sys.argv[3]
now you can call like below:
python my_app.py /path/to/input1.txt /path/to/input2.txt /path/to/output.txt
write a script that takes two optional boolean arguments,"--verbose‚" and ‚"--live", and two required string arguments, "base"and "pattern". Please set up the command line processing using argparse.
This is the code I have so far for the question, I know I am getting close but something is not quite right. Any help is much appreciated.Thanks for all the quick useful feedback.
def main():
import argparse
parser = argparse.ArgumentParser(description='')
parser.add_argument('base', type=str)
parser.add_arguemnt('--verbose', action='store_true')
parser.add_argument('pattern', type=str)
parser.add_arguemnt('--live', action='store_true')
args = parser.parse_args()
print(args.base(args.pattern))
The string arguments are not required by default, so you need to state that. Also the print statement that uses the arguments is incorrect.
#!/usr/bin/python
import argparse
if __name__=="__main__":
parser = argparse.ArgumentParser(description='eg $python myargs.py --base arg1 --pattern arg2 [--verbose] [--live]')
parser.add_argument('--base', required=True, type=str)
parser.add_argument('--pattern', required=True, type=str)
parser.add_argument('--verbose', action='store_true')
parser.add_argument('--live', action='store_true')
args = parser.parse_args()
print "args.base=" + str(args.base)
print "args.pattern=" + str(args.pattern)
print "args.verbose=" + str(args.verbose)
print "args.live=" + str(args.live)
the #!/usr/bin/python at the top enables the script to be called directly, though python must be located there (to confirm, type $which python), and you must set the file to have execute permission ($chmod +x myargs.py)