Question

1. Write a standalone function partyVolume() that takes accepts one argument, a string containing the name of a file. The objective of the function is to determine the a Volume object that is the result of many people at a party turning the Volume up and down. More specifically: the first line of the file is a number that indicates the initial value of a Volume object. The remaining lines consist of a single character followed by a space followed by a number. The character will be one of ‘U” or ‘D’ which stand for “up” and “down” respectively. The function will create a new Volume object and then process each line of the file by calling the appropriate method of the Volume object which changes the value of the Volume. The function then returns the final Volume object.   Guidelines/hints:
   1. This is a standalone function, it should NOT be inside (indented within) the class. It should be listed in the module after the Volume class and without indentation.
   2. Note that the first line of the file will be treated differently than all the other lines. Probably the easiest way to do this is to 1) open the file, 2) call the .readline() method (no s!) which reads a single line, the initial value of the Volume, then 3) call the .readlines() method which reads the rest of the lines. Item 2) will be used to set the initial Volume and 3) will be iterated over to represent turning the volume up and down some number of time.
   3. Make sure you return the final Volume object.

##### Volume #####

# set and get

>>> v = Volume()

>>> v.set(5.3)

>>> v

Volume(5.3)

>>> v.get()

5.3

>>> v.get()==5.3 # return not print

True

>>>

# __init__, __repr__, up, down

>>> v = Volume(4.5) # set Volume with value

>>> v

Volume(4.5)

>>> v.up(1.4)

>>> v

Volume(5.9)

>>> v.up(6) # should max out at 11

>>> v

Volume(11)

>>> v.down(3.5)

>>> v

Volume(7.5)

>>> v.down(10) # minimum must be 0

>>> v

Volume(0)

# default arguments for __init__

>>> v = Volume() # Volume defaults to 0

>>> v

Volume(0)

# can compare Volumes using ==

>>> # comparisons

>>> v = Volume(5)

>>> v.up(1.1)

>>> v == Volume(6.1)

True

>>> Volume(3.1) == Volume(3.2)

False

# constructor cannot set the Volume greater

# than 11 or less than 0

>>> v = Volume(20)

>>> v

Volume(11)

>>> v = Volume(-1)

>>> v

Volume(0)

>>>

##### partyVolume #####

>>> partyVolume('party1.txt')

Volume(4)

>>> partyVolume('party2.txt')

Volume(3.75)

>>> partyVolume('party3.txt')

Volume(0.75)

# make sure return not print

>>> partyVolume('party1.txt')==Volume(4) # return not print

True

>>> partyVolume('party2.txt')==Volume(3.75)

True

>>> partyVolume('party3.txt')==Volume(0.75)

True

use python3.7

Answer 1

Here is the completed code for this problem. Since you did not provide the Volume class, I have written this code based on my assumptions and doctests. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

Note: Please maintain proper code spacing (indentation), just copy the code part and paste it in your compiler/IDE directly, no modifications required.

#code

#required method, assuming Volume class is defined and is accessible
def partyVolume(filename):
    #opening file in read mode, assuming file exists
    file=open(filename,'r')
    #reading initial volume
    initial=float(file.readline())
    #creating a Volume object with initial volume
    v=Volume(initial)
    #looping through rest of the lines in file
    for line in file.readlines():
        #removing trailing/leading white spaces/newlines and splitting line by white
        #space to get a list of tokens
        line=line.strip().split(' ')
        #ensuring that length of resultant list is 2
        if len(line)==2:
            #reading first value as direction (U or D)
            dir=line[0].upper()
            #reading second value as float value
            value=float(line[1])
            if dir=='U':
                #turning volume up
                v.up(value)
            elif dir=='D':
                #turning volume down
                v.down(value)
    #closing file, saving changes
    file.close()
    #returning volume
    return v