Table of Contents

• 1  Q1: what does the following print?

• 2  Q2: modify Problem_Def to incorporate get_spacing as an instance method

class Problem_Def:
    """
    this class holds the specifcation for the domain,
    including the value of the porosity
    """

    nx: int
    ny: int
    poro: float
    wx: float
    wy: float

    def __init__(self, nx, ny, poro, wx, wy):
        self.nx = nx
        self.ny = ny
        self.poro = poro
        self.wx = wx
        self.wy = wy


def get_spacing(nx=4, ny=3, poro=0.4, wx=10, wy=20):
    the_prob = Problem_Def(nx, ny, poro, wx, wy)
    delx = the_prob.wx / the_prob.nx
    dely = the_prob.wy / the_prob.ny
    return delx, dely

Q1: what does the following print?

print(f"{get_spacing(nx=6)}")

(1.6666666666666667, 6.666666666666667)

Q2: modify Problem_Def to incorporate get_spacing as an instance method

that is, create a version of Problem_Def for which the following will work:

::

the_instance = Problem_Def() delx, dely = the_instance.get_spacing()

where the new constructor has the signature:

::

def __init__(self,nx=4,ny=3,poro=0.4,wx=10,wy=20):

…

class Problem_Def:
    """
    this class holds the specifcation for the domain,
    including the value of the porosity
    """

    nx: int
    ny: int
    poro: float
    wx: float
    wy: float

    def __init__(self, nx=4, ny=3, poro=0.4, wx=10, wy=20):
        self.nx = nx
        self.ny = ny
        self.poro = poro
        self.wx = wx
        self.wy = wy

    def get_spacing(self):
        delx = self.wx / self.nx
        dely = self.wy / self.ny
        return delx, dely


the_instance = Problem_Def(nx=6)
delx, dely = the_instance.get_spacing()
print(delx, dely)

1.6666666666666667 6.666666666666667