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Published inDec 2016
Reading LevelBeginner
PublisherPackt
ISBN-139781786463517
Edition1st Edition
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Authors (3):
Claus Führer
Claus Führer
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Claus Führer

Claus Führer is a professor of scientific computations at Lund University, Sweden. He has an extensive teaching record that includes intensive programming courses in numerical analysis and engineering mathematics across various levels in many different countries and teaching environments. Claus also develops numerical software in research collaboration with industry and received Lund University's Faculty of Engineering Best Teacher Award in 2016.
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Variable number of arguments


Lists and dictionaries may be used to define or call functions with a variable number of arguments. Let's define a list and a dictionary as follows:

data = [[1,2],[3,4]]    
style = dict({'linewidth':3,'marker':'o','color':'green'})

Then we can call the plot function using starred (*) arguments:

plot(*data,**style)

A variable name prefixed by * , such as *data in the preceding example, means that a list that gets unpacked in the function call is provided. In this way, a list generates positional arguments. Similarly, a variable name prefixed by **, such as **style in the example, unpacks a dictionary to keyword arguments. Refer to the following figure (Figure 7.1):

Figure 7.1: Starred arguments in function calls

You might also want to use the reverse process, where all given positional arguments are packed into a list and all keyword arguments are packed into a dictionary when passed to a function.

In the function definition, this is indicated by parameters prefixed...

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Scientific Computing with Python 3
Published in: Dec 2016Publisher: PacktISBN-13: 9781786463517

Authors (3)

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Claus Führer

Claus Führer is a professor of scientific computations at Lund University, Sweden. He has an extensive teaching record that includes intensive programming courses in numerical analysis and engineering mathematics across various levels in many different countries and teaching environments. Claus also develops numerical software in research collaboration with industry and received Lund University's Faculty of Engineering Best Teacher Award in 2016.
Read more about Claus Führer