GLIMSE OF EVERYTHING AT BASICS!!.txt

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PYTHON VARIABLES:
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'''
a=100               #single line coment
print("the number a is ",a)
a=input("enter a number:")
print("the number a again is ",a)
multiline
comment
'''
a, i = int(input("enter the value of a: ")), int(input("enter the value of i to find 'the ith power of a': "))
print("a**i =", a**i) #a power i
print("a%i=",a%i)
min=print("a is even") if (a%2==0) else print("odd")
a=0b0010 #binary
b=0o54  #octal
c=0x12C #hexadecimal
d="hello world"
print(d)
f=float(input("enter no in float:\t"))
print(f)
f=1.5e3
print("f=1.5e3",f,"can also be written like this!")
x=3+2j #j not i as per mathematics
print("real part is",x.real,"imaginary part is",x.imag,"the complex literal is ",x)

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CONTOL STRUCTURES:
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x=int(input("enter x:"))
if x>=90 and x<100: #and 
        print("O grade")
elif  x>=80 and x<90: #rem :
        print("A+ grade")
else:
        print("failed")
if "hello" in "My name is prabha! hello":
        print("found")
else:
        print("not found")
n=int(input("enter n:")) #sum
sum=float((n*(n+1))/2)
print("sum of n natural numbers:",sum)
sum=0
i=0
while(i<=n): #while loop #whille loop can have a else part too!!
        sum=sum+i
        i=i+1
print("sum of n natural numbers:",sum)
for ch in "hello":  #ch was never declared!!
    print(ch,end='') #in this case output will come in the same line adjacent to each other!!!!!
print("\n")
for i in range(-10,11,1): #start,end,step     #also end=end-step!!! #range(20),0-19 inc by step 1!!
    print(i,sep='\n')
# make use of pass,continue,break!!

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FUNCTIONS:
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#functions!!
'''' retutrn none is nothing is returned
    arguments-values,parameters-f() def
    required,keyword,anonymous or lambda,recursive'''
#def keyword is used!!
''' a global varaible can't be accessed without pasing them into a block else use global <variable> keyword'''
'''n=int(input("enter a no:"))
def fact(n):
    i=1
    f=1
    while(i<=n):
        f=f*i
        i=i+1
    return f
a=fact(n)
print("the factorial of",n,"is",a)'''
#does not necesarily need to return....nothing returns resuts o/p as NONE!
#default arguments in function defenition!
#in keyword argument order of call doesn't matter!
# def he(*arg) VARIABLE LENGTH ARGUMRNT
#lambda <Lf() name>=lambda <arguments>:<expression>
a=float(input("enter a floating point number:"))
print("abs(a):",abs(a)) #sign change
a=int(input("enter a  number:"))
print("chr(a):",chr(a)) #asci char
b=input("enter a  letter:")
print("ord(b):",ord(b)) #asci val
print("bin(a):",bin(int(a))) #to bin
print("type(a):",type(a),"\nid(a):",id(a))
#min(),max(),sum() in a list!
print("d-b",format(a,'b')) #decimal to other conversion!
print("d-o",format(a,'o'))
print("d-o",format(a,'x'))   
print("d-f",format(a,'f')) #decimal to FIXED POINT! 6prescision!
a=input("enter a f numebr:")
print("round(a)=",round(float(a)))
#pow()
#import math----> floor(),ceil(),sqrt()!!
#eval() --> evaluvates the expresssion or statment or the varaible!

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STRINGS AND STRING MANUPULATIONS:
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#strings are immutable!
#-ve index from last!
'''' int(x,2/10/8/16)''' #to decimal
''' format(x,b/x/o/f)''' #decimal to others!!
#str[ ]
a=input("enter a sentance:")
print("str length:",len(a)) #len()
b,c=input("enter the word to be replaced:"),input("enter the NEW word:")
print(a.replace(b,c)) #replace(old,new)
#del a
print(a *4) #repeats <str*num>
#splice operator<[start,end,stride]> #end=end-1!!!!!!
#formating strings %d,%s,%c (str%())
# .format() { } -placeholders.....str.format()
print(a.capitalize()) #.capitalixe()
print(a.lower()) #small
print(a.islower()) #if small
print(a.isupper()) #if upper
print(a.center(20,'$')) #.center(width,'symbol')
print(a.find("abi",0,10)) #.find(substr,start,end)
print(a.isalnum())#if alphanumerical
print(a.isalpha())# if alphabets
print(a.isdigit())#if nums
print(a.title()) #1st leteer CAPS
print(a.swapcase()) #swaps!
print(a.islower()) #small
print(a.islower())
''' .count and .find '''
#.counts substr .count(substr,start,end) 
'''in and not in''' #are call MEMBERSHIP OPERATORS!!

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LIST,TUPLES,SETS,DICTIOANRY:
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#LISTS is mutable!
a=[1,'hello',3.14159,[2,4,6]]
print(a," is my list")
print("length of a:",len(a));
a[0:4]=[1,2,3,4]
a[3]='yo'
#changing varaiables!
print(a," is my list")
print(a.append(5),'appended string')#.append() one element @once
print(a," is my appended list")
print(a.extend([6,7,8,9,10]),'extended string')#.extendd([ ]) more than one element @once
print(a," is my extended list")
print(a.insert(9,'hello I am replaced at index 9'))#.insert(index,element)
print(a," is my list")
del a[0]
'''index know'''#del lname(index)/(range=>from to) 
print(a,'deleted oth index')
del a[0:6]#5th index
print(a,'deleted o to 6-1th index!! index')
print(a.remove(8),'elemnt 8 is removed')#index unknown!!! element known!!!
print(a," is my list")
b=a.pop(1) #index know!
print(b,'is the pooped up element')
a.clear()
print(a," is my list without elemnets!!.")#clear() everything juts keeps th EMPTY list!!
a=list(range(1,11,2)) #list from range()
print(a," is my list using range!")
c=a.copy()
print(a," is my list",c,"is the copy")
''' .count(substr,start,end).......counts the string'''# .count(value) in list counts the number of similar values! 
''' similar to str.find() returns the index of the first elemennt! '''#.index(element)
a.extend([3,3,3,3,3,3])
print(a," is my list after extend!!")
count=a.count(3)
print(count,'  is the count of no of  3 in the list!')
i=a.index(3)
print(i," is the index of 1st no 3 in list after appending!!")
del a[6:12]
print("the list after deltion from index 6 to 11(12-1) is",a)
a.reverse()
print(a,'is the reversed string!')
#.sort() ......default ascending,reverse is SET as true then descending!
maxy=max(a) #max(list)
miny=min(a) #min(list)
sumy=sum(a)#sum(list)
print("the max is {} and the minimum is {} and sum of the list is {}".format(maxy,miny,sumy))


#TUPULES is immutable! [ ]----->() unordered hence no indices
'''  list and tupules can be createed in empty a=[] , a=()'''
a=tuple(a)#tuple from list!
print(a,"a is a tuple!")
#list and tuples are classes in python!
del a
t=tuple(list(range(0,30,2)))
'''tuple assignement (a,b)=(1,2)'''
def max_min(t):
    max_=max(t)
    min_=min(t)
    return (max_,min_)
(mx_val,mn_val)=max_min(t)
print("the max is {} and min is {} of the tuple {}".format(mx_val,mn_val,t))

#SETS are mutable an unique! and sets can have diff data type!
t=set(t)
print(t,"is a set")
#.add()
#A.union(B) |
#A.intersection(B) &
#A.symmetric_difference(B) ^ (A&B)-(A|B)
#A.difference(B) A-B
#is_prime

''' THEY ARE
    DATA STRUCTURE!!!'''
#DICTIONARIES!!
#var={key:value,}
# create var{}
#so, while the syntax for creating an empty set using {} appears similar to creating an empty dictionary,
#Python interprets it as an empty dictionary. If you want to create an empty set, it's safer to use set() or {} with a space inside (i.e., { }).
''' list=[z**2 for z in range(1,11)]
    dict={x:x*2 for x in range(1,11}'''
#acess using dict[key]
#adding extra element dict[new key]=new val/element!