Chapter 3 Python Basics

CHAPTER 3

Python Basics

Keynote

3.1 Identifiers Le Keywords

Python cu case sensitive (ca ngan le ca hme a thleidan mi) language a si. Python identifier cu variable, function, class, module, asiloah object dang hngalh/thleidan nak caah hman mi min a si.

Identifiers ser nak phunglam pawl:

• Alphabet (ca) asiloah underscore (_) in aa thawk a hau.

• A hnu ah letters, _, le digits (nambar) an zul kho.

• keyword cu identifier in hman khawh a si lo.

Keywords dihlak cu lowercase (ca hme) in an si (Note: False, None le True ti lo). Python nih Table 3.1 ah hmuh sak mi keywords 33 a ngei.

Table 3.1 Keywords list
False	continue	from	not
None	def	global	or
True	del	if	pass
and	elif	import	raise
as	else	in	return
assert	except	is	try
break	finally	lambda	while
class	for	nonlocal	with
yield

A tanglei statements hmang in Python keywords list kha na print khawh:

checking keyword list

import keyword # makes the module 'keyword' available
print(keyword.kwlist) # syntax modulename.object/function

---

3.2 Python Types

Python nih data types phun 3 a support:

• Basic Types:
  • int, float, complex, bool, string, bytes
• Container Types:
  • list, tuple, set, dict
• User-defined types:
  • class

Hi hna lak ah, basic types kong cu hi chapter ah a tling tein fianh a si lai. Container types kong cu a tawi nak in fianh a si lai. Container type pakhat cio caah a dang tein chapter ser a si, cuka ah cun a tling tein fianh a si lai. User-defined types cu hi chapter ah fianh a si lai lo. Chapter 17 ah zeitin dah ser le hman ding an si ti kha fianh a si.

---

3.2.1 Basic Types

Basic types aa dangdang hna i tahchunhnak cu a tanglei ah pek an si:

• int cu binary, decimal, octal, hexadecimal in langhter khawh a si.
• binary cu 0b/0B in aa thawk, octal cu 0o/0O in, hex cu 0x/0X in aa thawk (tahchunhnak: 0b10111, 156, 0o432, 0x4A3).
• float cu fractional asiloah exponential form in langhter khawh a si (tahchunhnak: 314.1528, 3.141528e2, 3.141528E2).
• complex ah real le imaginary part an um (tahchunhnak: 3 + 2j, 1 + 4J).
• bool cu Boolean values pahnih lak ah pakhat paoh a si kho i an pahnih in ca lian in an i thawk (tahchunhnak: True, False).
• string cu Unicode characters a hlawm a si i thlen khawh a si lo (immutable), ' ', " ", asiloah """ """ chung ah chiah a si. 'Rosanna', "Rosanna", """Rosanna""".
• bytes nih binary data a aiawh.

bytes example

b'\xa1\xe4\x56' # hex values a1a456 a ngei mi bytes 3 a aiawh

Data pakhat i a type kha type() tiah auh mi function hmang in chek khawh a si, a tanglei bantuk in:

checking type of data using type() function

print(type(35)) # <class 'int'> tiah a print/langhter
print(type(3.14)) # <class 'float'> tiah a print/langhter

3.2.2 Integer Le Float Ranges

• int cu a duh zahzah a ngan a si kho (limit a um lo).

integer example

a = 123
b = 1234567890
c = 123456789012345678901234567890

Python nih arbitrary precision integers a ngei. Cucaah na duh zah a ngan mi integers na ser khawh. Cun, integers cung ah arithmetic operations (tuaknak) na tuah tik ah overflow/underflow (limit luan/tlhum lo) kong ah lungretheih a hau lo.

Floats cu computer chung ah IEEE 754 standard ning in 64-bit double-precision values in binary ah chiah/langhter an si. Hi standard ning in cun, float nih a ngeih khawh mi a ngan bik value cu 1.8 x 10^308 hrawng a si. Hi nak in a ngan mi nambar cu inf (short for infinity - tawpnak ngei lo) in langhter a si.

Floats tampi cu binary form in 'a dik thlap in' (exactly) langhter khawh an si lo. Cucaah a chung i chiah ning (internal representation) cu a taktak value he 'aa lo nawn' (approximation) in chiah a si tawn.

A taktak value le an langhter mi value i an i dannak cu a hme tuk, cucaah buaibainak nganpi a chuahter tawn lo.

3.3 Variable Type Le Assignment

Variable i a type kha khiah/chimh cia a hau lo. Execution a tuah lio ah variable i a type cu zeitin dah hman a si timi context zoh in amah tein a lak (inferred). Cucaah Python cu dynamically-typed language tiah auh a si.

Variable type

a = 25 # a i type cu int tiah a lak/hngalh
a = 31.4 # a i type cu float tiah a lak/hngalh
a = 'Hi' # a i type cu str tiah a lak/hngalh

Variable pakhat i a type kha type() timi built-in function hmang in chek khawh a si.

str variable

a = 'Job Kaa'
print(type(a)) # type cu str tiah a report/langhter lai

A fawi mi variable assignment (value pek ning):

assignment example

a = 10
pi = 3.14
name = 'Rosanna'

Variables tampi a voikhat ah assignment tuah ning (value pek ning):

multiple assignment example

a = 10 ; pi = 31.4 ; name = 'Rosanna' # ; hi statement separator in hman a si
a, pi, name = 10, 3.14, 'Rosanna'
a = b = c = d = 5

3.3.1 Arithmetic Operators

Arithmetic Operators: +, - , * , /, %, //, **

Arithmetic Operators

a = 4 / 2 # true division a tuah i float 2.0 a chuah
a = 7 % 2 # % nih a taang mi (remainder) 1 a chuah
b = 3 ** 4 # ** nih 3 a voi 4 nak a chuah (exponentiation)
c = 4 // 3 # // nih fractional part (a cheu) hlawt in quotient 1 a chuah

In-place assignment operators nih arithmetic operations (tuaknak) caah shortcut (lam tawi) ṭha taktak a pek. Cu hna cu +=, -=, *=, /=, %=, //=, **= an si.

In-place assignment

a **= 3 # a = a ** 3 he aa khat
b %= 10 # b = b % 10 he aa khat

3.3.2 Operation Nuances (Tuaknak I A Sining Pawl)

Floor division a//b kan tuah tik ah, a chuak mi result (a phi) cu quotient (a cheu mi a phi taktak) nak in a niam deuh mi asiloah aa khat mi integer (nambar tling) a ngan bik kha a si. // cu floor division operator tiah an auh.

(Note: Negative nambar a um tik ah a niam lei/thlang lei ah a kal. Tahchunhnak ah -10 kha 3 in cheu ah -3.33 a si, asinain floor division nih cun -3.33 nak in a niam deuh mi -4 tu a laak).

Floor Division

print(10 // 3) # 3 a chuah
print(-10 // 3) # -4 a chuah
print(10 // -3) # -4 a chuah
print(-10 // -3) # 3 a chuah
print(3 // 10) # 0 a chuah
print(3 // -10) # -1 a chuah
print(-3 // 10) # -1 a chuah
print(-3 // -10) # 0 a chuah

-10 // 3 ah, -10 hmuh ding in 3 i a let cu -3.333 a si, a floor value cu -4 a si. 10 // -3 ah, 10 hmuh ding in -3 i a let cu -3.333 a si, a floor value cu -4 a si. -10 // -3 ah, -10 hmuh ding in -3 i a let cu 3.333 a si, a floor value cu 3 a si.

print( ) cu function a si i screen cung ah output langhter ding ah hman a si. Lam phunphun in hman khawh a si. Cu hna cu Chapter 7 ah fianh a si lai.

a % b timi operation cu a - (b * (a // b)) tiah tuak a si. Hihi a tanglei tahchunhnak pawl hman hian fawi tein hngalh khawh a si:

print functions

print(10 % 3) # 1 a chuah
print(-10 % 3) # 2 a chuah
print(10 % -3) # -2 a chuah
print(-10 % -3) # -1 a chuah
print(3 % 10) # 3 a chuah
print(3 % -10) # -7 a chuah
print(-3 % 10) # 7 a chuah
print(-3 % -10) # -3 a chuah

a % b cu a - (b * (a // b)) tiah tuak a si caah, -10 % 3 cu -10 - (3 * (-10 // 3)) tiah tuak a si i, 2 a chuak. 10 % -3 cu 10 - (-3 * (10 // -3)) tiah tuak a si i, -2 a chuak. -10 % -3 cu -10 - (-3 * (-10 // -3)) tiah tuak a si i, -1 a chuak.

Mathematical rule a / b x c le a x c / b hi an i khat tawn, asinain a zungzal in a si lo (Computer chung ah cun).

Mathematical rule

# a tanglei expressions hna hi an result (a phi) aa khat
a = 300 / 100 * 250
a = 300 * 250 / 100

# Asinain, a tanglei hna hi cu an i khat lo
b = 1e210 / 1e200 * 1e250
b = 1e210 * 1e250 / 1e200 # INF (tawpnak ngei lo) a chuak

True cu 1 a si i False cu 0 a si caah, an pahnih in belh (add) khawh an si.

True and False

a = True + True # 2 a chuah
b = True + False # 1 a chuah

3.4 Precedence Le Associativity

Arithmetic expression pakhat chung ah operators tampi hman an si tik ah, hman mi operators pawl i an precedence (priority - biapi ah chiah in tuak hmasa ding) cung ah hngat in tuak a si.

Priority a sang bik in a niam bik lei operators pawl (PEMDAS):

Precedence of operators

( ) # Parentheses (Kuek)
** # Exponentiation (A let)
*, /, //, % # Multiplication, Division (Tuk, Cheu)
+, - # Addition, Subtraction (Belh, Thwn)

Precedence (priority) aa khat mi operators pahnih an um a si ahcun, associativity hmang in biakhiahnak tuah a si (aho dah tuah hmasa ding ti kha).

Operator pakhat cio nih left to right associativity (Keh lei in Orh lei) asiloah right to left associativity (Orh lei in Keh lei) an ngei.

Tahchunhnak ah c = a * b / c ah, * kha / nak in tuah hmasa a si, a ruang cu arithmetic operators nih left to right associativity an ngeih caah a si (Keh lei in a rat tik ah * nih a hmuh hmasa).

Python operators dihlak, an priority le an associativity cazin tling cu Appendix A ah pek a si.

3.4.1 Conversions (Thlen Ning)

Mixed mode operations (Cawh-nuk in tuahnak):

• int le float karlak ah tuah a si ahcun float a chuak.
• int le complex karlak ah tuah a si ahcun complex a chuak.
• float le complex karlak ah tuah a si ahcun complex a chuak.

Numeric type pakhat in a dang pakhat ah thlen ding caah int( ), float( ), complex( ) le bool( ) timi built-in functions hna hi hman khawh an si.

Type conversions:

Type conversions

int(float/numeric string) # float asiloah numeric string in int ah thlen
int(numeric string, base) # numeric string kha base a um mi int ah thlen
float(int/numeric string) # int asiloah numeric string in float ah thlen
float(int) # int in float ah thlen
complex(int/float) # complex ah thlen (imaginary part 0 in)
complex(int/float, int/float) # complex ah thlen (real le imaginary he)
bool(int/float) # int/float in True/False (1/0) ah thlen
str(int/float/bool) # string ah thlen
chr(int) # int he aa tlak mi character (ca) ah thlen

int( ) nih a cheu mi (quotient) i a point hnu (decimal portion) kha a hlonh, cucaah zero lei ah a round (a tling mi ah a thlen) zungzal.

int()

a = int(3.33) # 3 a chuah
b = int(-3.33) # -3 a chuah

3.4.2 Built-in Functions (A Chung Um Cia Functions)

Python nih built-in functions (amah chung ah a um cia mi) tampi a ngei, cu hna cu program chung khoika hmun paoh ah hman khawh an si. Screen cung ah output langhter ding caah kan hman tawn mi print( ) function zong kha built-in function pakhat a si.

Built-in function pakhat paoh kong he pehtlai in bawmhnak (help) hmuh na duh ahcun help(function) kha hman khawh a si.

Nambar he hman tawn mi Built-in functions pawl cu a tanglei ah pek an si:

Built-in functions

abs(x) # x i a absolute value (a man taktak) a chuah
pow(x, y) # x a voi y nak (x raised to y) a chuah
min(x1, x2,...) # arguments lak ah a hme bik a chuah
max(x1, x2,...) # arguments lak ah a ngan bik a chuah
divmod(x, y) # (x // y, x % y) kha pair (a kop) in a chuah
round(x [,n]) # point hnu ah n digits um ding in x kha a round
bin(x) # x he aa khat mi binary a chuah
oct(x) # x he aa khat mi octal a chuah
hex(x) # x he aa khat mi hexadecimal a chuah

A tanglei Python program nih hi built-in functions cheukhat hman ning a hmuhsak:

Built-in functions

a = abs(-3) # a ah 3 a chiah (assign)
print(min(10, 20, 30, 40)) # 10 a print/langhter
print(hex(26)) # 1a a print/langhter (Python taktak ah cun 0x1a tiah a lang)

3.4.3 Built-in Modules

Built-in functions leng ah, Python nih built-in modules tampi a pek. Module pakhat cio ah functions tampi an um. Mathematical operations a sang deuh mi tuah ding caah built-in modules a simi math, cmath, random, decimal chung i functions pawl kha hman khawh an si.

Built-in modules

math - hman a ṭhahnem mi mathematics functions tampi.
cmath - complex numbers cung ah operations tuahnak functions.
random - random number (nambar can-u-nan) sernak he aa tlai mi functions.
decimal - arithmetic operations a dik thlap in (precise) tuahnak functions.

math module chung i Mathematical functions pawl:

Mathematical functions in math module

pi, e # constants pi le e i an values (man)
sqrt(x) # x i square root
factorial(x) # x i factorial
fabs(x) # float x i absolute value (a man taktak)
log(x) # x i natural log (base e hman in log)
log10(x) # x i base-10 logarithm
exp(x) # e a voi x nak (e raised to x)
trunc(x) # integer ah thlen/tan (point hnu hlonh)
ceil(x) # x nak in a ngan deuh asiloah aa khat mi integer a hme bik
floor(x) # x nak in a niam deuh asiloah aa khat mi integer a ngan bik
modf(x) # x i a fractional (a cheu) le integer parts (a tling) pawl

round( ) timi built-in function cu decimal places (point hnu) a biaki mi zah tiang round tuah khawh a si, asinain math module i library functions trunc( ), ceil( ) le floor( ) pawl nih cun decimal places zero (point hnu um lo) tiang lawng an round zungzal.

math module chung i Trigonometric functions pawl:

Trigonometric functions in math module

degrees(x) # radians in degrees ah thlen
radians(x) # degrees in radians ah thlen
sin(x) # x radians i sine
cos(x) # x radians i cosine
tan(x) # x radians i tan
sinh(x) # x i hyperbolic sine
cosh(x) # x i hyperbolic cosine
tanh(x) # x i hyperbolic tan
acos(x) # x i cos inverse, radians in
asin(x) # x i sine inverse, radians in
atan(x) # x i tan inverse, radians in
hypot(x, y) # sqrt(x * x + y * y) (Hypotenuse tuaknak)

random module chung i Random number generation functions pawl:

Random number generation functions from random module

random( ) # 0 le 1 karlak ah random number (nambar can-u-nan)
randint(start, stop) # start le stop karlak (range) ah random number
seed( ) # random number sernak hram (seed) caah atu lio caan (current time) kha a hman
seed(x) # random number sernak hram (seed) caah x kha a hman

Module pakhat chung i functions pawl hman khawh ding caah, import statement hmang in module kha import (lak) kan tuah a hau.

A tanglei Python program nih math module le random module chung i functions cheukhat hman ning a hmuhsak:

Using functions from math and random modules

import math
import random
print(math.factorial(5)) # 120 a print/langhter
print(math.degrees(math.pi)) # 180.0 a print/langhter
print(random.random( )) # 0.8960522546341796 a print/langhter

Built-in functions tampi an um i built-in module pakhat cio chung ah functions tampi an um fawn. Functions pawl i an min philh a fawi te. A tanglei program hi hman in a ran nak in kan hmuh/chek khawh hna:

Getting list of built-in functions

import math
print(dir(__builtins__)) # builtins hmailei le hnulei ah underscore pahnih cio an um
print(dir(math))

3.5 Container Types

Container types tiah chim tik ah a tlangpi in values tampi hmun khat ah chiah ṭi kha a chim duh mi a si. Basic types aa dangdang hna i tahchunhnak cu a tanglei ah pek an si:

Container types

# list cu index in kawl khawh mi, thilri a phunphun chiah ṭi nak a si
[10, 20, 30, 20, 30, 40, 50, 10], ['She', 'sold', 10, 'shells']

# tuple cu thlen khawh lo mi (immutable) hlawm a si
('Rosanna', 34, 4500.55), ('Python With Joe', 350, 195.00)

# set cu values aa dang cio (unique) lawng chiah ṭi nak a si
{10, 20, 30, 40}, {'Rosanna', 34, 45000}

# dict cu key-value pairs hlawm a si, a unique mi key kha '' chung ah chiah a si
{'ME101' : 'Strength of materials', 'EE101' : 'Electronics'}

List le tuple chung i values pawl cu an umnak hmun (position) hmang in lak khawh an si. Set chung i values pawl cu for loop hmang in lak khawh an si (hihi Chapter 6 ah fianh a si lai). Dictionary chung i values pawl cu key hmang in lak khawh an si. Hihi a tanglei program ah hmuhsak a si:

Accessing values in container types

lst = [10, 20, 30, 20, 30, 40, 50, 10]
tpl = ('Python With Joe', 350, 195.00)
s = {10, 20, 30, 40}
dct = {'ME101' : 'SOM', 'EE101' : 'Electronics'}
print(lst[0], tpl[2]) # 10 195.0 a print/langhter
print(dct['ME101']) # SOM a print/langhter

3.5.1 Python Type Jargon (Biafang Hman Mi Pawl)

Python types kong chim tik ah a tanglei biafang pawl hi hman an si tawn:

• Collection - container types caah hman mi biafang a si.
• Iterable - loop hman in a chung thil pakhat hnu pakhat kal khawh mi/lanh khawh mi collection a si.
• Ordered collection - elements (a chung thil) kha kan khumh ning tein an um. Cucaah index (a umnak hmun) hmang in lak khawh an si.
• Unordered collection - elements kha kan khumh ning tein an um lo. Cucaah element pakhat hi khoika hmun ah dah a um ti kan chim kho lo. Cucaah position based index hmang in lak khawh a si lo.
• Sequence - ordered collection caah hman mi biafang a si.
• Immutable - thlen khawh lo mi collection (unchangeable).
• Mutable - thlen khawh mi collection (changeable).

Atu ah cun kan hmuh ciami types pawl hi zeibantuk sining dah an ngeih ti zoh hna usih:

• String - ordered collection, immutable, iterable.
• List - ordered collection, mutable, iterable.
• Tuple - ordered collection, immutable, iterable.
• Set - unordered collection, mutable, iterable.
• Dictionary - unordered collection, mutable, iterable.

3.5.2 Comments Le Indentation

Comments cu # in an i thawk.

Comments begin with #

# calculate gross salary (gross salary tuaknak)
gs = bs + da + hra + ca 
si = p * n * r / 100 # calculate simple interest (simple interest tuaknak)

Catlang tampi a um mi comments (Multi-line comments) pawl cu ''' (triple single quotes) asiloah """ (triple double quotes) chung ah ṭial a hau.

Multi-line comments should be written in a pair of ''' or \

''' Additional program: Calculate bonus to be paid
URL: [https://github.com/rose1996iv/PythonWithJoe](https://github.com/rose1996iv/PythonWithJoe) ([https://github.com/rose1996iv/PythonWithJoe](https://github.com/rose1996iv/PythonWithJoe))
Author: Joseph, Date: 7 Dec 2025 '''

Indentation (catlang hram ṭhawn) hi a biapi tuk! Na duh poh in hmang hlah. A tanglei code nih 'Unexpected indent' error a chuahter lai.

Indentation matters! Don’t use it casually. Following code will report an error 'Unexpected indent'.

a = 20 
  b = 45 # Indentation a herh lo nak hmun ah tuah a si caah Error a piah lai

Multi-lining (Catlang Tampi In Ṭial)

Statements an sau tuk a si ahcun, catlang tampi ah ṭhen in ṭial khawh an si. A tawpnak catlang dah ti lo, a dang catlang donghnak paoh ah \ (backslash) chiah a hau.

Multi-lining

total = physics + chemistry + maths + \
english + myanmar + history + \
geography + civics

[ ], { }, asiloah ( ) chung ah statements kha catlang tampi (multi-line) in ṭial a si tik ah \ (backslash) hman a hau lo.

Multi-line

days = [ 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 
'Friday', 'Saturday', 'Sunday' ]

3.6 Classes Le Objects

Python ah type paoh cu class an si. Cucaah int, float, complex, bool, str, list, tuple, set, dict pawl hi classes an si dih. Hi hna cu hman ding in a um cia mi (ready-made) classes an si. Python nih kanmah tein class ser (user-defined classes) zong a kan onh, hihi Chapter 18 ah kan hmuh te lai.

Object cu class in ser a si. Class nih thil pahnih a fianter — cu class in ser mi object cu zeidah a lawh lai (a sining) le cu object laknak le tawlrelnak caah hman khawh mi methods (functions) pawl an si.

Class pakhat in objects tampi ser khawh a si. Class in object ser a si tik ah, class i instance ser a si tiah chim a si.

Class nih min a ngei, asinain objects nih min an ngei lo. Objects nih min an ngeih lo caah, memory chung i an umnak addresses (hmun) hmang in auh asiloah hngalh an si.

A cunglei chim mi dihlak hi a tanglei program hmang hian hneksak/hmuh khawh a si. A sullam ṭha tein hngalh ding in Observation (Hmuhning) kha zoh.

All the above statements can be verified through the following program.

a = 30
b = 'Good'
print(a, b) # 30 Good tiah a print
print(type(a), type(b)) # <class 'int'> <class 'str'> tiah a print
print(id(a), id(b)) # 1356658640 33720000 (Memory address pawl) tiah a print
print(isinstance(a, int), isinstance(b, str)) # True True tiah a print

3.7 Python Object Reference Visualization (Python Object Pawl Hmuhning)

Python ah variables nih memory chung i objects an hngaih/lak ning hngalh hi a biapi tuk.

Key Concept (A Biapi Mi):

• Python ah cun, variables cu memory chung i a um mi objects a kawhhmuhtu references (asiloah pointers) an si. Values (a man) kha anmah chung ah an chiah lo, value umnak memory location (hmun) tu kha an kawk.

Memory Reference Breakdown

A tanglei table nih diagram chung i references pawl kha a tial:

Variable Name	Reference ID (Address)	Points To (Object Type)	Object Value	Object Memory Address
a	1356658640	int object	30	1356658640
b	33720000	str object	Good	33720000

Observation (Hmuhning):

• Variable a nih reference ID 1356658640 a ngei, cucu Integer Object 30 i a address he aa khat.
• Variable b nih reference ID 33720000 a ngei, cucu String Object 'Good' i a address he aa khat.

Hi program chung ah objects pahnih kan ser — pakhat cu ready-made class a simi int in le a dang pakhat cu ready-made class a simi str in kan ser.

int type object nih 30 a ngei, cun str type object nih 'Good' a ngei.

Object pahnih hna hi min an ngei lo. Memory chung i an addresses 1356658640 le 33720000 kha a le b chung ah chiah an si.

Hi addresses pawl cu built-in function a simi id( ) hmang in hmuh khawh an si. Program na execute (tuahter) tik ah addresses aa dang na hmuh kho men (computer aa dan ah aa dang kho).

a le b nih addresses an ngeih caah, cu addresses ah a um mi objects kha an refer (kawk/hngaih) tiah chim a si. A fawi nak in chim ahcun objects a kawktu pointers an si.

a le b nih an refer mi objects i an type kha built-in function a simi type( ) hmang in hmuh khawh a si.

a hi class int i instance a si le si lo kha built-in function a simi isinstance( ) hmang in chek khawh a si.

Multiple Objects

A tanglei program hi zoh hmanh:

Multiple Objects

a = 3
b = 3
print(id(a), id(b)) # 1356658640 1356658640 tiah a print (an id aa khat)
print(a is b) # True tiah a print (object khat an si caah)

a = 30 # atu ah cun a nih object dang a refer cang
print(id(a)) # 1356659072 (address thar) tiah a print

int object pahnih kan ser maw? A si lo. int object chung i um mi value (3) aa khat mi a si caah, int object 1 lawng ser a si. a le b nih int object a um cia mi kha an hngaih/kawk veve. Cucaah id(a) le id(b) nih address aa khat an chuahnak a si.

Hihi is operator hmang in hneksak khawh a si. a le b nih object khat an hngaih caah True a chuah.

a chung ah value thar chiah kan i zuam tik ah, value aa dang (30) a si caah int object thar ser a si. Atu ah cun a nih int object thar kha a hngaih cang, asinain b nih cun int object value 3 kha a hngaih rih ko.

a nih value 3 a ngei mi int object a hngaih tiah chim nak in, a cu int object a si, asiloah 3 cu a ah assigned kan tuah tiah chim a si tawn.

Programmers tampi nih a le b cu int variables an si tiah an zumh, asinain atu ah cun a si lo ti kan hngalh cang.

Problem 3.1

Integer types le operators hman ning hmuhsaknak.

Program

Problem 3.1

# use of integer types (integer types hman ning)
print(3 / 4)
print(3 % 4)
print(3 // 4)
print(3 ** 4)

a = 10 ; b = 25 ; c = 15 ; d = 30 ; e = 2 ; f = 3 ; g = 5 
w = a + b - c 
x = d ** e 
y = f % g 
print(w, x, y)
h = 99999999999999999
i = 54321
print(h * i)

Output

Output

0.75
3
0
81
20 900 3
5432099999999999945679

Tips

• ¾ nih 0 a chuah lo (Python 3 ah cun 0.75 a chuah, a tling lo mi nambar zong a tuak khawh).
• Catlang khat chung ah statements tampi an um ahcun ; (semicolon) hman in ṭhen ding a si.
• print(w, x, y) nih values pawl kha space (karkhat) in ṭhen in a print/langhter.

Problem 3.2

float, complex le bool types hman ning le cu hna he hman khawh mi operators hmuhsaknak.

Program

Problem 3.2

# use of float (float hman ning)
i = 3.5
j = 1.2 
print(i % j) # 1.1 a chuah (approx)

# use of complex (complex number hman ning)
a = 1 + 2j 
b = 3 *(1 + 2j)
c = a * b
print(a)
print(b)
print(c)
print(a.real) # a i a real part (1.0)
print(a.imag) # a i a imaginary part (2.0)
print(a.conjugate( )) # a i a conjugate (1-2j)
print(a)

# use of bool (boolean hman ning)
x = True
y = 3 > 4 
print(x) # True
print(y) # False

Output

Output

1.1
(1+2j)
(3+6j)
(-9+12j)
1.0
2.0
(1-2j)
(1+2j)
True
False

Tips

• % (Modulus operator) hi floats cung zong ah a ṭuan kho.
• Complex number pakhat in real le imag part kha lak khawh an si.
• Condition (sining) pakhat chek a si tik ah True asiloah False in thlen a si.

Problem 3.3

Number type pakhat in a dang ah thlen ning hmuhsaknak.

Program

Problem 3.3

# convert to int (int ah thlen)
print(int(3.14)) # float in int ah (point hnu a hlonh)
a = int('485') # numeric string in int ah
b = int('768') # numeric string in int ah
c = a + b 
print(c)
print(int('1011', 2)) # binary in decimal int ah thlen
print(int('341', 8)) # octal in decimal int ah thlen
print(int('21', 16)) # hex in decimal int ah thlen

# convert to float (float ah thlen)
print(float(35)) # int in float ah
i = float('4.85') # numeric string in float ah
j = float('7.68') # numeric string in float ah
k = i + j 
print(k)

# convert to complex (complex ah thlen)
print(complex(35)) # int in complex ah
x = complex(4.85, 1.1) # numeric string in complex ah
y = complex(7.68, 2.1) # numeric string in complex ah
z = x + y 
print(z)

# convert to bool (bool ah thlen)
print(bool(35)) # True (0 a si lo mi paoh True an si)
print(bool(1.2)) # True
print(int(True)) # 1
print(int(False)) # 0

Output

Output

3
1253
11
225
33
35.0
12.53
(35+0j)
(12.53+3.2j)
True
True
1
0

Tips

• Binary numeric string, octal numeric string asiloah hexadecimal numeric string pawl kha a he aa khat mi decimal integer ah thlen khawh a si. Hi thil hi float caah tuah khawh a si lo.
• complex ah thlen tik ah argument pakhat lawng hman a si ahcun, imaginary part cu 0 ah chiah a si.
• Zero a si lo mi nambar (int asiloah float) paoh cu True tiah lak a si. 0 cu False tiah lak a si.

Problem 3.4

Built-in mathematical functions (A chung um cia mi mathematical functions) hman ning hmuhsaknak program.

Program

Problem 3.4

# built-in math functions (math functions hman ning)
print(abs(-25)) # 25 (Negative kha positive ah a thlen/Absolute value)
print(pow(2, 4)) # 16 (2 a voi 4 nak)
print(min(10, 20, 30, 40, 50)) # 10 (A hme bik)
print(max(10, 20, 30, 40, 50)) # 50 (A ngan bik)
print(divmod(17, 3)) # (5, 2) (Quotient 5 le Remainder 2 kha tuple in a chuah)
print(bin(64), oct(64), hex(64)) # Binary, Octal, Hexadecimal ah a thlen hna
print(round(2.567), round(2.5678, 2)) # 3 (A tling ah round a tuah), 2.57 (Point hnu 2 tiang round a tuah)

Output

Output

25  
16
10
50
(5, 2)
0b1000000 0o100 0x40
3 2.57

Tips

• divmod(a, b) nih a kop in (a // b, a % b) a chuah.
• bin( ), oct( ), hex( ) nih binary, octal le hexadecimal he aa khat mi values an chuah.
• round(x) nih decimal point hnu ah 0 places (zeihmanh a um lo) tiang round tuah ding a si tiah a laak.

Problem 3.5

Math module chung i functions hmang in program ṭial ning.

Program

Problem 3.5

# mathematical functions from math module (math module chung i mathematical functions)
import math
x = 1.5357
print ( math.pi, math.e) # pi le e i an man pawl
print(math.sqrt( x)) # x i a square root
print(math.factorial(6)) # 6 i a factorial
print(math.fabs(x)) # x i a absolute value (float in)
print(math.log(x)) # x i a natural log
print(math.log10(x)) # x i a base-10 logarithm
print(math.exp(x)) # e a voi x nak (e raised to power x)
print(math.trunc(x)) # Integer ah thlen (point hnu hlonh)
print(math.floor(x)) # A niam deuh mi integer ah round (1)
print(math.ceil(x)) # A ngan deuh mi integer ah round (2)
print(math.trunc(-x)) # Integer ah thlen (-1)
print(math.floor(-x)) # A niam deuh mi integer ah round (-2)
print(math.ceil(-x)) # A ngan deuh mi integer ah round (-1)
print(math.modf(x)) # Fractional part le Integer part ṭhen in tuple in a chuah

Output

Output

3.141592653589793 2.718281828459045
1.2392336341465238
720
1.5357
0.42898630314951025
0.1863063842699079
4.644575595215059
1
1
2
-1
-2
-1
(0.5357000000000001, 1.0)

Tips

• floor( ) nih negative infinity lei (a niam lei) ah a round, ceil( ) nih positive infinity lei (a san lei) ah a round, trunc( ) nih 0 lei ah a round (a niam lei asiloah a san lei siseh 0 umnak lei hoih in).
• Positive numbers caah cun trunc( ) cu floor( ) he an i lo.
• Negative numbers caah cun trunc( ) cu ceil( ) he an i lo.
• modf( ) nih nambar kop (f, i) a chuah, cu tik ah x = f + i a si i 0 <= f < 1 a si.

Problem 3.6

Float le integer random numbers (nambar can-u-nan) sernak program ṭial tuah.

Program

Problem 3.6

# random number operations using random module (random module hman ning)
import random 
import datetime

# datetime.time() hmang in seed tuah
# (Note: A ṭha deuh mi cu datetime.datetime.now() hman asiloah a lawng in chiah a si)
random.seed(datetime.time( )) 

print(random.random( )) # 0.0 le 1.0 karlak ah random float a chuah
print(random.random( )) # 0.0 le 1.0 karlak ah random float a chuah
print(random.randint(10, 100)) # 10 le 100 karlak ah random integer a chuah

Tips

• seed( ) hi random number generator hram thoknak (initialize) caah hman a si.
• random.random( ) nih 0.0 in 1.0 karlak ah a um mi float value a chuah.
• random.randint(a, b) nih a le b karlak ah a um mi integer value a chuah (a le b zong aa tel).

Output

Output

0.23796462709189137
0.5442292252959519
57

Tips

• random module kha import tuah a hau.
• Random number generation logic kha atu lio caan (current time) he seed kan tuah ahcun, program kan execute (tuahter) fatin random numbers aa dang mi kan hmuh lai.
• random.seed( ) kha parameter tel lo in kan hman ahcun amah tein current time kha seed caah a hman.

Problem 3.7

A tanglei hna hi string, list, tuple, set asiloah dictionary an si le si lo zeitin dah na hngalh/thleidan lai?

{10, 20, 30.5}
[1, 2, 3.14, 'Nagpur']
{12 : 'Simple', 43 : 'Complicated', 13 : 'Complex'}
"Check it out!"
3 + 2j

Program

Problem 3.7

# determine type of data
print(type({10, 20, 30.5}))
print(type([1, 2, 3.14, 'Nagpur']))
print(type({12 : 'Simple', 43 : 'Complicated', 13 : 'Complex'}))
print(type("Check it out!"))
print(type(3 + 2j))

Output

Output

<class 'set'>
<class 'list'>
<class 'dict'>
<class 'str'>
<class 'complex'>

Tips

• type( ) cu built-in function a si i, zeibantuk data (built-in, container asiloah user-defined) paoh i a type (a phun) kha a hngalh/thleidan khawh.

Exercises

[A] A tanglei biahalnak hna hi phi tuah:

• a. Variable a le b i an values (man) kha thlen (swap) nak program ṭial tuah. Variable pathumnak hman a ngah lo. a le b cung ah arithmetic (tuaknak) tuah a ngah lo.
• b. math module chung i a um mi trigonometric functions hman ning hmuhsaknak program ṭial tuah.
• c. 10 le 50 karlak ah random numbers (nambar can-u-nan) 5 sernak program ṭial tuah. Seed value ah 6 hmang tuah. Cun, program na execute (tuahter) fatin seed value aa thlen nakhnga time (caan) he pehtlai in tuah tuah?
• d. trunc( ), floor( ) le ceil( ) hna i an i dannak hngalh ding ah -2.8, -0.5, 0.2, 1.5 le 2.9 pawl hmang in program ṭial tuah.
• e. City (Khuapi) pakhat i a lum-sik (temperature) kha Fahrenheit in chiah law (suum law), cucu Centigrade ah thlen nak program ṭial tuah. An pahnih in print (langhter) tuah.
• f. Triangle (Tukum) pakhat i a sir (sides) a, b, c ngeih a si. A kil (angles) pathum tuak nak program ṭial tuah, a phi cu a niam bik integer (next integer) ah round tuah. A tanglei formulae hi hmang:

\[ a^2 = b^2 + c^2 - 2bc.cos A, b^2 = a^2 + c^2 - 2ac.cos B, c^2 = a^2 + b^2 - 2ab.cos C\]

[B] A tanglei rian pawl hi zeitin dah na tuah hna lai:

• a. 2 + 3j i a imaginary part kha print tuah.
• b. 4 + 2j i a conjugate kha la/chuah.
• c. Binary 1100001110 he aa khat mi decimal kha print tuah.
• d. Float value 4.33 kha numeric string ah thlen.
• e. 29 kha 5 in cheu tik i a chuak mi integer quotient (a cheu tu) le remainder (a taang mi) kha lak ding.
• f. Decimal 34567 he aa khat mi hexadecimal kha lak ding.
• g. 45.6782 kha decimal place pahnihnak tiang round-off tuah.
• h. 3.556 chung in 4 lak ding.
• i. 16.7844 chung in 17 lak ding.
• j. 3.45 kha 1.22 in cheu tik i a remainder (a taang mi) lak ding.

[C] A tanglei pawl lak ah a khoi mi hi dah variable min caah hman a ngah lo (invalid), cun zeiruang ah dah?

Column 1	Column 2	Column 3	Column 4
BASICSALARY	_basic	basic-hra	#MEAN
group.	422	pop in 2020	over
timemindovermatter	SINGLE	hELLO	queue.
team'svictory	Plot#3	2015_DDay

[D] A tanglei expressions pawl hi tuak hna:

• a. 2 ** 6 // 8 % 2
• b. 9 ** 2 // 5 - 3
• c. 10 + 6 - 2 % 3 + 7 - 2
• d. 5 % 10 + 10 - 23 * 4 // 3
• e. 5 + 5 // 5 - 5 * 5 ** 5 % 5
• f. 7 % 7 + 7 // 7 - 7 * 7

[E] A tanglei expressions pawl hi tuak hna:

• a. min(2, 6, 8, 5)
• b. bin(46)
• c. round(10.544336, 2)
• d. math.hypot(6, 8)
• e. math.modf(3.1415)

[F] A tanglei pawl hi a kop in thleidan/peh hna:

Section A	Section B
a. complex	1. \
b. Escape special character (Special character hrialnak)	2. Container type
c. Tuple	3. Basic type
d. Natural logarithm	4. log( )
e. Common logarithm	5. log10( )

---

---

Comments