Chapter 4

#Exercise 4.1 Run the program on your system and see what numbers you get. Run the program more than once and see what numbers you get.


#The function random returns a random float between 0.0 and 1.0 (including 0.0 but not 1.0)

import random

for i in range(10):
    x=random.random()
    print(x)

#The output of this program displays random numbers
#0.4184357119673642
#0.6297955102447773
#0.6061678855186424
#0.6153135553282525
#0.6766973528876312
#0.6445292394094398
#0.8013163399117574
#0.19139696551055974
#0.10143315716528511
#0.4250712145676583
# After rerunning this program again the output was
#0.02458150217996713
#0.2765057775875218
#0.21092102938726598
#0.38367827954821265
#0.25575302933073296
#0.5222072687698197
#0.6217626728991629
#0.02943314326290125
#0.31136277049841565
#0.4125183265713611

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#Exercise 4.2 Move the last line of this program to the top, so the function call appears beforethe definitions. Run the program and see what error message you get.
repeat_lyrics()


def repeat_lyrics():
    print_lyrics()
    print_lyrics()

def print_lyrics():
    print("I'm a lumberjack, and I'm okay.")
    print("I sleep all night and I work all day.")

#output
#Traceback (most recent call last):
 # File "/home/saravanan/Documents/python/eg4.py", line 2, in <module>
  #  repeat_lyrics()
#NameError: name 'repeat_lyrics' is not defined

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#Exercise 4.3 Move the function call back to the bottom and move the definition of print_lyrics after the definition of repeat_lyrics. What happens when you run this program?


def print_lyrics():
    print("I'm a lumberjack, and I'm okay.")
    print("I sleep all night and I work all day.")

def repeat_lyrics():
    print_lyrics()
    print_lyrics()

repeat_lyrics()

#No errors. The program runs successfully.

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Exercise 4.4 What is the purpose of the ”def” keyword in Python?
b) It indicates the start of a function

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Exercise 4.5 What will the following Python program print out?
d) ABC Zap ABC

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#Exercise 4.6 Rewrite your pay computation with time-and-a-half for overtime and create a function called computepay which takes two parameters (hours and rate).
def computepay(hours,rate):
    if int(hours)>40:
        extra=float(rate)*float((int(hours)-40)*1.5)
        pay=(float(rate)*float(40))+extra
    else:
        pay=float(hours)*float(rate)
    print(pay)


h=input('Enter Hours:')
r=input('Enter rate:')
computepay(h,r)

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#Exercise 4.7 Rewrite the grade program from the previous chapter using a function called computegrade that takes a score as its parameter and returns a grade as a string.

def computegrade(i):
    try:
        h=float(i)
        if h!=str():
            if h>=0.0 and h<=1.0:
                if h>0.6 and h<=0.7:
                    return 'D'
                elif h>0.7 and h<=0.8:
                    return 'C'
                elif h>0.8 and h<=0.9:
                    return 'B'
                elif h>0.9:
                    return 'A'
                else:
                    return 'F'
            else:
                return 'Bad score'
    except:
        return 'Bad score'


s=input('Enter Score:')
a=computegrade(s)
print(a)