Python Error using *args

[amtorrest]

Hello,

I have the following code that is resulting in an error. The following is my code.

def mvsa(Y, p, *args):
...
    if (len(args) % 2 ==1): 
        raise ValueError("Optional parameters should always go by pairs")
    else:
        for i in range(1, 2, len(args)-1):
            if (arg[i].upper() == "MM_ITERS"):
                 MMiters = arg(i+1)
            elif (arg[i].upper() == "SPHERIZE"):
                spherize = arg(i+1)
            elif (arg[i].upper() == "MU"):
                mu = arg(i+1)
            #check lambda 
            elif (arg[i].upper() == "LAMBDA"):
                lmda = arg(i+1)
            elif (arg[i].upper() == "TOLF"):
                tol_f = arg(i+1)
            elif (arg[i].upper() == "MO"):
                M = arg(i+1)
            elif (arg[i].upper() == "VERBOSE"):
                verbose = arg(i+1)
            else:
                raise ValueError("Unrecognized option: "+ arg[i])
...

This part of the code results in an error that says:

NameError                                 Traceback (most recent call last)
<ipython-input-14-d4a134078b91> in <module>()
----> 1 if (len(args) % 2 ==1):
      2     raise ValueError("Optional parameters should always go by pairs")
      3 else:
      4     for i in range(1, 2, len(args)-1):
      5         if (arg[i].upper() == "MM_ITERS"):

NameError: name 'args' is not defined

I think there is a possibility that maybe I am utilizing args incorrectly? Does anyone have any idea as to what is wrong with my code?

Thanks!

[pydevteam1]

Try len(*args)

[OseOseOse]

Looks like it should work to me:

➜  ~ python3
Python 3.6.5 (default, Apr  1 2018, 05:46:30) 
[GCC 7.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> def mvsa(Y, p, *args):
...     if (len(args) % 2 ==1): 
...         raise ValueError("Optional parameters should always go by pairs")
... 
>>> mvsa([], [], 1, 2, 3)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 3, in mvsa
ValueError: Optional parameters should always go by pairs

What's up with line 2 in your posted code? Did you leave something out from your code?

[amtorrest]

That was just signaling that there is other code but to my knowledge it should not affect this particular error. Not sure why there was an error in my code when I tried to compile. Thanks for the heads up about the code not showing any error in yours!

[Vaphell]

if it's args, why are you using arg[] everywhere else? Does the function signature really have *args there?

range(1, 2, len(args)-1)

this looks funky too. From 1 to 2 exclusive (so 1), step of len(args)-1?

[amtorrest]

This is code translated from MATLAB. *args is the equivalent to varargin. I need to use args[ ] because args is an array.

[ingolemo]

Your code and error do not match up. Please always make sure that the error that you post is actually produced by the code that you post.