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For todayβs practice make use of notebook module1-day3.ipynb created in your enviroment. Shut down kernel for all previous notebooks by right cliking on notbeook on left hand side file browser.
%load_problem squareWrite a function square to compute the square of a number.
>>> square(4)
16
You can verify your solution using:
%verify_problem square
# your code here
def square(x):
return x*x
%verify_problem squareFound 2 checks
β verify square(2)
β verify square(4)
π Congratulations! You have successfully solved problem square!!setentece = "These are some wise or otherwise words!"setentece.startswith("This")Falsesetentece.startswith("These")Truesetentece.endswith("?")Falsesetentece.split() # it splits given text into words/small subsets of text.
# it creates a list and returns['These', 'are', 'some', 'wise', 'or', 'otherwise', 'words!']setentece.split("or")['These are some wise ', ' otherwise w', 'ds!']comma_separated = "symbol,value,high,low,volume"comma_separated.split(",") # spliting on comma on a csv text, you will get the fields separated['symbol', 'value', 'high', 'low', 'volume']path = "/home/jupyter-vikrant/"path.split("/")['', 'home', 'jupyter-vikrant', '']tab_separated = "one\ttwo\tthree"print(tab_separated)one two threetab_separated.split()['one', 'two', 'three']multiline = """one
two
three
four"""multiline'one\ntwo\nthree\nfour'print(multiline)one
two
three
fourmultiline.split() # split without any argument or parameter will split on white spaces
# white spaces include space, tab, new line or mixture of it['one', 'two', 'three', 'four']words = ["one", "two", "three", "four"]" ".join(words)'one two three four'sentence = " ".join(words)sentence'one two three four'line = " some line from a file which has white space at start and also at end "line' some line from a file which has white space at start and also at end 'line.strip() # will strip trailing white spaces'some line from a file which has white space at start and also at end'text = "one two"text.strip() # it will remove only trailing spaces'one two'problems
On a website login only alphanumeric usernames are allowed. a string is stored in a variable username. How will you check if username is as per rules?
A sentence has hyphen between every two words. >>> sentence = "Yet-another-sentence-with-nothing-in-it" How can you transorm it such that there will be space between every two words.
A path to file is given for a linux system. on a linux system path seperator is β/β
>>> path = "/home/vikrant/training/day1.html"How will you find only name of file from given path?
Using string methods can you find extension of a file if filename is stored in a variable filename = "hello.xlsx"
sentence = " hello method chaining! "
sentence.strip().split()[-1]
#--->------>----->------>----->'chaining!'path = "/home/vikrant/training/day1.html"path.split("/")['', 'home', 'vikrant', 'training', 'day1.html']path.split("/")[-1]'day1.html'def find_filename(path):
"""This will work only on linux/unix/mac
"""
return path.split("/")[-1]find_filename("/home/vikrant/trainings/2025/arcesium-finop-dec25/hello.csv")'hello.csv'filename = "hello.xlsx" # in this etension is xlsxzippedfile = "training.tar.gz" # extension is gzfilename.split(".")[-1]'xlsx'def find_extension(filename):
return filename.split(".")[-1]find_extension(zippedfile)'gz'find_extension(filename)'xlsx'username1 = "vikrant123"
username2 = "vikrant_patil"username1.isalnum()Trueusername2.isalnum()Falsedef check_username(username):
"""This function will check if username is alpha numeric !
"""
return username.isalnum()check_username("vikrant323")Truecheck_username("vikrant_patil")Falsesentence = "Yet-another-sentence-with-nothing-in-it"words = sentence.split("-")words['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']words[0]'Yet'words[1]'another'words[-1]'it'words['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']nums = [1, 2, 3, 4, 5, 6] # this actual list does not have comma in ittext_list = "[1, 2, 3, 4, 5, 6]"text_list[0]'['words['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']1212"12"'12'["one", "two", "three", "four"]['one', 'two', 'three', 'four']print(words)['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']nums = [1, 2, 3, 4, 5, 6]nums.index(4) # 3words['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']words.index("in")5words.count("Yet")1ones = [1, 1, 1, 1, 1, 1]ones.count(1)6ones.count(2)0nums[0]1nums[3] # given an index what is the item at that index4nums.index(4) # given an item what is the index of that item3words[0] # what is the word at 0 index'Yet'words.index("in") # what is the index of in!5empty = [] empty.append(0)# append an item at lastempty[0]empty.append("one")empty[0, 'one']empty.append(2)empty[0, 'one', 2]empty.insert(0, -1) # insert at given location insert(location, value)empty[-1, 0, 'one', 2]empty.remove('one')ones[1, 1, 1, 1, 1, 1]ones.remove(1) # will always remove first occurence of the given itemones[1, 1, 1, 1, 1]observe that which methods return some value and which do not return
words['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']empty[-1, 0, 2]empty.append(1)
empty.append(1)empty[-1, 0, 2, 1, 1]empty = []empty.append(1)empty[1, 1, 1]empty = []
empty.append(1)
empty[1]words['Yet', 'another', 'sentence', 'with', 'nothing', 'in', 'it']words.pop() # will pop last item (it will return that item) and also remove it from the list'it'words['Yet', 'another', 'sentence', 'with', 'nothing', 'in']words.reverse() # reverse the list in placewords['in', 'nothing', 'with', 'sentence', 'another', 'Yet']problem
What will this print?
x = 10 def foo(): x = 20
foo() print(x)
x = 10
def foo():
x = 20
foo() # these statements are outside function, how? look at indentation
print(x) # this is from global context/namespace/scope10What will this print?::
x = 10
def foo(): print(x)
foo()
x = 10
def foo():
print(x) # if variable is not defined locally it will read (only read) from global
foo()10What will this print?::
x = 10
def foo(): x = x + 1
foo() print(x)
x = 10
def foo():
x = x + 1
foo()
print(x)--------------------------------------------------------------------------- UnboundLocalError Traceback (most recent call last) Cell In[148], line 6 3 def foo(): 4 x = x + 1 ----> 6 foo() 7 print(x) Cell In[148], line 4, in foo() 3 def foo(): ----> 4 x = x + 1 UnboundLocalError: cannot access local variable 'x' where it is not associated with a value
[1, 2, 3] + [4, 5][1, 2, 3, 4, 5]words['in', 'nothing', 'with', 'sentence', 'another', 'Yet']words.append("hello") # this will modify original listwords + ["hello"] # will new create a new list['in', 'nothing', 'with', 'sentence', 'another', 'Yet', 'hello', 'hello']words = ['in', 'nothing', 'with', 'sentence', 'another', 'Yet']
print("addition", words + ["hello"])
print("original list", words)
words.append("hello")
print("origianl list after append", words)addition ['in', 'nothing', 'with', 'sentence', 'another', 'Yet', 'hello']
original list ['in', 'nothing', 'with', 'sentence', 'another', 'Yet']
origianl list after append ['in', 'nothing', 'with', 'sentence', 'another', 'Yet', 'hello']What will this print?::
x = [1, 1, 1]
def appendzero(y):
y.append(0)
appendzero(x)
print(x)x = [1, 1, 1]
def appendzero(y):
y.append(0)
appendzero(x)
print(x)[1, 1, 1, 0]x = [1, 1, 1]
def appendzero(y):
return y + [0]
z = appendzero(x)
print(x)
print(z)[1, 1, 1]
[1, 1, 1, 0]y = [1, 1, 1]
def appendzero(y): # we defined function..
y.append(0)
print(y)[1, 1, 1]y = [1, 1, 1]
def appendzero(y): # we defined function..
y.append(0)
appendzero(y)
print(y)[1, 1, 1, 0]x = [1, 1, 1]
a = x # this is not copy this is alias
b = x[:] # or use method x.copy()
def appendzero(y):
y.append(0)
appendzero(b)
print(x)
print(b)[1, 1, 1]
[1, 1, 1, 0]def sumofsqaures(a, b, c):
return square(a) + square(b) + square(c)
def sumofcubes(a, b, c):
return cube(a) + cube(b) + cube(c)
def square(x):
return x*x
def cube(x):
return x*x*x
def sumof(a, b, c, func):
return func(a) + func(b) + func(c)sumofsqaures(4, 6, 9)133sumof(4, 6, 9, square)133sumofcubes(3, 5, 7)495sumof(3, 5, 7, cube)495x, y, z = 10, 20 , 5sumofcubes(x, y, z)9125sumof(x, y, z, cube)9125words = ["one", "two", "three", "four", "five", "six"]max(words)'two'def add(a, b):
return a + badd(2, 3) # arguments by position5max(words, key=len)'three'min(words, key=len)'one'sorted(words)['five', 'four', 'one', 'six', 'three', 'two']sorted(words, key=len)['one', 'two', 'six', 'four', 'five', 'three']records = [
("TATA", 200.0, 5.5),
("INFY", 2000.0, -5),
("RELIANCE", 1505.5, 50.0),
("HCL", 1200, 70.5)
]records[0]('TATA', 200.0, 5.5)max(records)('TATA', 200.0, 5.5)len("one")3r = ('TATA', 200.0, 5.5)def get_value(r):
return r[1]
def get_gain(r):
return r[2]records[('TATA', 200.0, 5.5),
('INFY', 2000.0, -5),
('RELIANCE', 1505.5, 50.0),
('HCL', 1200, 70.5)]max(records, key=get_value)('INFY', 2000.0, -5)min(records, key=get_value)('TATA', 200.0, 5.5)max(records, key=get_gain)('HCL', 1200, 70.5)sorted(records, key=get_value)[('TATA', 200.0, 5.5),
('HCL', 1200, 70.5),
('RELIANCE', 1505.5, 50.0),
('INFY', 2000.0, -5)]max("one", "two", "three", "four", "five") # dictionary order'two'max("one", "two", "three", "four", "five", key=len)'three'('TATA', 200.0, 5.5) ('HCL', 1200, 70.5) ('RELIANCE', 1505.5, 50.0) ('INFY', 2000.0, -5)
|
get_value() get_value() get_value() get_value()
200.0 1200.0 1505.5 2000.0
words['one', 'two', 'three', 'four', 'five', 'six']for word in words:
WORD = word.upper()
print(WORD)ONE
TWO
THREE
FOUR
FIVE
SIXfor char in "this statement":
print(char)t
h
i
s
s
t
a
t
e
m
e
n
tfor char in "this statement":
print(char, end=",")t,h,i,s, ,s,t,a,t,e,m,e,n,t,primes = [1, 2, 3, 5, 7, 11, 13, 17, 19]for p in primes:
print(p*p)1
4
9
25
49
121
169
289
361sqr = []
for p in primes:
psqr = p*p
sqr.append(psqr)sqr[1, 4, 9, 25, 49, 121, 169, 289, 361]def mysum(numbers): # first code block
s = 0
for i in numbers: # i will take values 1, 2, 3, 5, ....
s = s + i
return s # the moment you come back to indentation level which was for loop
mysum(primes)78primes[1, 2, 3, 5, 7, 11, 13, 17, 19]for p in primes:
print(p)1
2
3
5
7
11
13
17
19for x in primes:
print(x)1
2
3
5
7
11
13
17
19for w in words:
print(w)one
two
three
four
five
sixfor word in words:
print(word)one
two
three
four
five
sixproduct which finds product of all elements from a list. >>> product([3, 2, 4])
24factorial to find factorial of a number. Hint : Use function range(1,n) to generate numbers from 1 to n. if you put for loop on this range(1,n) it will give numbers 1 to n >>> factorial(5)
120findlens which finds lengths of every word from a given list of words. >>> findlens(["one", "two", "three"])
[3, 3, 5]