arguments

Fix Python – Can you list the keyword arguments a function receives?

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I have a dict, which I need to pass key/values as keyword arguments.. For example..
d_args = {‘kw1’: ‘value1’, ‘kw2’: ‘value2’}
example(**d_args)

This works fine, but if there are values in the d_args dict that are not accepted by the example function, it obviously dies.. Say, if the example function is defined as def example(kw2):
This is a prob….

Fix Python – In Python, can I call the main() of an imported module?

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In Python I have a module myModule.py where I define a few functions and a main(), which takes a few command line arguments.
I usually call this main() from a bash script. Now, I would like to put everything into a small package, so I thought that maybe I could turn my simple bash script into a Python script and put it in the package.
So, how do ….

Fix Python – How to pass arguments to a Button command in Tkinter?

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Suppose I have the following Button made with Tkinter in Python:
import Tkinter as Tk
win = Tk.Toplevel()
frame = Tk.Frame(master=win).grid(row=1, column=1)
button = Tk.Button(master=frame, text=’press’, command=action)

The method action is called when I press the button, but what if I wanted to pass some arguments to the method action?
I have tr….

Fix Python – How do I define a function with optional arguments?

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I have a Python function which takes several arguments. Some of these arguments could be omitted in some scenarios.
def some_function (self, a, b, c, d = None, e = None, f = None, g = None, h = None):
#code

The arguments d through h are strings which each have different meanings. It is important that I can choose which optional parameters to ….

Fix Python – Which exception should I raise on bad/illegal argument combinations in Python?

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I was wondering about the best practices for indicating invalid argument combinations in Python. I’ve come across a few situations where you have a function like so:
def import_to_orm(name, save=False, recurse=False):
“””
:param name: Name of some external entity to import.
:param save: Save the ORM object before returning.
:param ….

[Fixed] *args calling plt.plot() for each optional argument

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I’m having some trouble with passing an arbitrary number of arguments to plt.plot(). For each argument I try to pass via *args my function calls plt.plot() two times creating duplicates for each optional argument. The read_n_plot function is meant to read some datafile, spit out the data as lists, and create a plot of said data. If I want to create a plot of an XRD standard for a crystal I want to make it easily distinguishable from whatever experimental data I’m comparing it with.
From what I understand *args is a tuple containing all the arguments passed to my function. But I can’t seem to figure out how to pass everything inside *args as is, and not calling plt.plot(arg1) -> plt.plot(arg2) -> etc
Got any hints I could try?
Here is my code:
import matplotlib.pyplot as plt

#def read_n_plot(datafile, color, thickness, style = ‘-‘, *args):
def read_n_plot(datafile, *args, **kwargs):
vinkel = []
intensitet = []
with open(datafile, encoding=’utf8′, errors=’ignore’) as f:
if datafile.endswith(‘.int’):
next(f); next(f)
lines = f.readlines()
for line in lines:
if line and line[0].isalpha():
continue
data = line.split()
theta, counts = float(data[0]), float(data[1])
vinkel.append(theta)
intensitet.append(counts)
intensitet_norm = [i/max(intensitet) for i in intensitet]
plt.plot(vinkel, intensitet_norm, label = datafile, *args, **kwargs)
return vinkel, intensitet_norm

plt.figure(figsize=(16,9))
read_n_plot(‘NaCl_data.xy’, ‘k’, ‘–‘, lw = 1.0)
plt.legend(loc=’best’)
plt.xlabel(r’$2\theta$’)
plt.xlim(0, 65)
plt.ylabel(‘Intensitet (a.u.)’)
plt.tick_params(left=None)
plt.yticks([])
plt.show()

Example below uses standard powder XRD data for NaCl. It seems the ‘–‘ argument for linestyle didn’t get through at all. The legend says there are two plots.
NaCl XRD data duplicate: