generate number of random numbers that have not repeat in a given range in python

random.sample(range(1, 16), 3)
[11, 10, 2]

get element, sublist and length of a list using python

d = range(10)
>>> d
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]


>>> d[9]
9


>>> d[-1]
9


>>> d[0:9]
[0, 1, 2, 3, 4, 5, 6, 7, 8]


>>> d[0:-1]
[0, 1, 2, 3, 4, 5, 6, 7, 8]


>>> len(d)
10

Matrix in python

There are no inbuilt function for define matrix. You can define the matrix as a list of list as follow

table= [ [ 0 for i in range(6) ] for j in range(6) ]
print table

result

[[0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0]]

make a list of class objects

class Person(object):
    """__init__() functions as the class constructor"""
    def __init__(self, name=None, job=None, quote=None):
        self.name = name
        self.job = job
        self.quote = quote
       
print
# make a list of class Person(s)
personList = []
personList.append(Person("Payne N. Diaz", "coach", "Without exception, there is no rule!"))
personList.append(Person("Mia Serts", "bicyclist", "If the world didn't suck, we'd all fall off!"))
personList.append(Person("Don B. Sanosi", "teacher", "Work real hard while you wait and good things will come to you!"))
personList.append(Person("Hugh Jorgan", "organist", "Age is a very high price to pay for maturity."))
personList.append(Person("Herasmus B. Dragon", "dentist", "Enough people can't find work in America!"))
personList.append(Person("Adolph Koors", "master-brewer", "Wish you were beer!"))
personList.append(Person("Zucker Zahn", "dentist", "If you drink from the fountain of knowledge, quench your thirst slowly."))



print "Show one particular item:"
print personList[0].name
print
print "Sort the personList in place by job ..."
import operator
personList.sort(key=operator.attrgetter('job'))
print "... then show all quotes and who said so:"
for person in personList:
    print "\"%s\"  %s (%s)" % (person.quote, person.name, person.job)
   
print
print "Show the quote(s) from any dentist:"
look = 'dentist'
for person in personList:
    if look in person.job:
        # title() capitalizes the job's first letter
        print "%s %s: \"%s\"" % (person.job.title(), person.name, person.quote)
       
print
print "What the heck did the person named Sanosi say?"
look = "Sanosi"
for person in personList:
    if look in person.name:
        print "%s: \"%s\"" % (person.name, person.quote)

for loops in python

for num in range(10,20):  #to iterate between 10 to 20
   for i in range(2,num): #to iterate on the factors of the number
      if num%i == 0:      #to determine the first factor
         j=num/i          #to calculate the second factor
         print '%d equals %d * %d' % (num,i,j)
         break #to move to the next number, the #first FOR
   else:                  # else part of the loop
      print num, 'is a prime number'