2-dars: O'zgaruvchilar va ma'lumot turlari

Dars

Davomiyligi: 90 daqiqa Maqsad: Python turlari va o'zgaruvchilar bilan ishlash.

1. O'zgaruvchi yaratish

name = "Akmal"
age = 22
height = 1.75
is_student = True

Tur belgilash kerak emas — Python avtomatik.

2. Asosiy turlar

Tur	Misol
int	42, -10, 0
float	3.14, -0.5
str	"Akmal", 'Hello'
bool	True, False
None	None
list	[1, 2, 3]
dict	{"key": "value"}
tuple	(1, 2, 3)
set	{1, 2, 3}

3. int va float

x = 42          # int
y = 3.14        # float
z = -5          # int
w = 1.5e10      # float (scientific)

Cheksiz katta: Python int — chegarasiz.

big = 10 ** 100  # OK!

C'da int 4 byte, lekin Python — istalgancha katta.

4. str (string)

a = "Salom"
b = 'World'
c = """Bir nechta
qatorli matn"""

# F-string
name = "Akmal"
greeting = f"Salom, {name}!"

Apostrof yoki qo'shtirnoq — bir xil.

String operatorlar

s = "Hello"
print(len(s))           # 5
print(s + " World")     # konkatenatsiya
print(s * 3)            # "HelloHelloHello"
print(s[0])             # 'H'
print(s[-1])            # 'o'
print(s[1:4])           # 'ell' (slice)
print("ello" in s)      # True

5. bool

a = True
b = False

# 0, "", [], None — Falsy
# Boshqalari — Truthy

if 0:
    print("0 truthy")   # Bu ishlamaydi
if "":
    print("'' truthy")  # Bu ham
if [1, 2]:
    print("list truthy") # Ishlaydi

6. None

x = None

if x is None:
    print("Bo'sh")

C: NULL. JavaScript: null. Python: None.

== o'rniga is ishlatish tavsiya etiladi.

7. type() — turni tekshirish

x = 42
print(type(x))           # <class 'int'>

print(type(3.14))         # <class 'float'>
print(type("Akmal"))      # <class 'str'>
print(type(True))         # <class 'bool'>
print(type(None))         # <class 'NoneType'>
print(type([1, 2]))       # <class 'list'>

isinstance() — yaxshiroq

x = 42
if isinstance(x, int):
    print("int")

8. Tur o'zgartirish

# String → int
n = int("42")           # 42
n = int("3.14")         # XATO!
n = int(3.14)            # 3

# String → float
f = float("3.14")        # 3.14

# Int/float → string
s = str(42)              # "42"
s = str(3.14)            # "3.14"

# Bool
b = bool(0)              # False
b = bool(1)              # True
b = bool("")             # False
b = bool("hello")        # True

# Int → bool
b = bool(0)              # False
b = bool(-5)             # True (har 0 dan boshqasi True)

9. Bir nechta o'zgaruvchi

# Bir vaqtda
a, b, c = 1, 2, 3

# Bir xil qiymat
x = y = z = 0

# Swap
a, b = b, a    # C'da temp kerak edi!

Swap Python'da — bir qator!

10. Constants (konstantalar)

Python'da rasmiy const yo'q. Konventsiya — KATTA HARF:

PI = 3.14159
MAX_USERS = 100
DATABASE_URL = "..."

Texnik jihatdan o'zgartirilishi mumkin, lekin uslub bo'yicha — yo'q.

11. Naming conventions

# Yaxshi
user_name = "Akmal"        # snake_case (o'zgaruvchi, funksiya)
MAX_VALUE = 100             # SCREAMING_SNAKE_CASE (konstanta)

# Class — keyingi darslarda
class Student:              # PascalCase
    pass

Reserved keywords:

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

12. f-string formatlash

name = "Akmal"
age = 22
pi = 3.14159

# Asosiy
print(f"Salom, {name}!")

# Aniqlik
print(f"Pi: {pi:.2f}")              # 3.14
print(f"Pi: {pi:.5f}")              # 3.14159

# Maydon kengligi
print(f"|{name:10}|")               # |Akmal     |
print(f"|{name:>10}|")              # |     Akmal|
print(f"|{name:^10}|")              # |  Akmal   |

# Raqamlar
print(f"|{age:5d}|")                # |   22|
print(f"|{age:05d}|")               # |00022|

# Ifoda
print(f"{2 + 3}")                   # 5
print(f"{name.upper()}")            # AKMAL
print(f"{age * 2}")                 # 44

# Debug (Python 3.8+)
print(f"{age=}")                    # age=22

13. Maxsus belgilar (escape)

print("Birinchi\nIkkinchi")          # \n yangi qator
print("Tab\tafter")                  # \t tab
print("Quote: \"text\"")             # \" qo'shtirnoq
print("Backslash: \\")               # \\ backslash

# Raw string (escape ishlamaydi)
print(r"C:\Users\Akmal")             # \U va boshqalar e'tiborsiz

14. Math amallar

+ - * /
**     # daraja: 2 ** 10 = 1024
//     # butun bo'lish: 7 // 2 = 3
%      # qoldiq: 7 % 2 = 1

# Boshqa funksiyalar
abs(-5)        # 5
round(3.7)     # 4
round(3.14159, 2)  # 3.14
min(1, 2, 3)   # 1
max(1, 2, 3)   # 3
sum([1, 2, 3]) # 6

math moduli

import math

math.pi        # 3.141592...
math.e         # 2.718...
math.sqrt(25)  # 5.0
math.pow(2, 10) # 1024.0
math.log(10)   # 2.302... (ln)
math.log2(8)   # 3.0
math.log10(100) # 2.0
math.sin(math.pi / 2)  # 1.0
math.factorial(5) # 120

15. random moduli

import random

random.random()           # 0.0 - 1.0
random.randint(1, 10)     # 1-10 (inclusive)
random.choice(["a","b","c"])  # birini tanlash
random.shuffle([1,2,3])   # aralashtirish

16. To'liq misol

# personal_info.py

name = input("Ism: ")
age = int(input("Yosh: "))
height = float(input("Bo'y (m): "))
city = input("Shahar: ")

# Calculations
birth_year = 2026 - age
height_cm = height * 100
age_in_days = age * 365

# Type check
print(f"\n=== Ma'lumotlar ===")
print(f"Ism: {name} ({type(name).__name__})")
print(f"Yosh: {age} ({type(age).__name__})")
print(f"Bo'y: {height} m = {height_cm:.0f} cm")
print(f"Shahar: {city}")
print(f"Tug'ilgan: {birth_year} yil")
print(f"Yashagan kunlar: {age_in_days}")

# Bool
is_adult = age >= 18
is_tall = height > 1.80

print(f"\nKattalar: {is_adult}")
print(f"Bo'yli: {is_tall}")

Topshiriqlar

1 — Turlar

turlar.py — beshta har xil turdagi o'zgaruvchi yarating (int, float, str, bool, None) va har birini qiymati bilan birga turini (type()) chop eting.

2 — Aylantirish

convert.py — quyidagi tur o'zgartirishlarni namoyish qiling va har birining natijasini chop eting:

• string → int (so'ng natijaga 5 qo'shing)
• float → int (kasr qismi tashlanadi)
• int → string (so'ng matn bilan biriktiring)
• string → float (so'ng 2 ga ko'paytiring)

3 — Math

math_demo.py — foydalanuvchidan doira radiusini so'rab, math modulidan foydalangan holda quyidagilarni hisoblang va :.2f bilan chiqaring:

• doira yuzasi va perimetri
• shar sirti va hajmi

4 — Random

random_demo.py — random modulini o'rganing:

• tasodifiy float (random()) va butun son (randint) chiqaring
• ro'yxatdan tasodifiy element tanlang (choice)
• olti yoqli zar tashlashni simulyatsiya qiling
• 6 ta tasodifiy lotereya raqamini yaratib chiqaring

5 — F-string

format.py — Dars matnidagi barcha format misollarini sinab ko'ring.

6 — Swap

swap.py — ikkita o'zgaruvchi qiymatini vaqtinchalik o'zgaruvchisiz almashtiring (Python'ning ko'p qiymatli belgilashidan foydalaning). So'ng uchta o'zgaruvchini ham bir qatorda aylantirib ko'ring.

7 — BMI kuchli

bmi_full.py — vazn, bo'y va yoshni so'rab, BMI va ideal vaznni (bo'y² × 22) hisoblang. Natijalarni f-string maydon kengligi bilan chiroyli jadval ko'rinishida chiqaring va BMI kategoriyasini aniqlang.

8 — Kvadrat tenglama

quadratic.py — a, b, c koeffitsientlarini so'rab, kvadrat tenglamani yeching. Diskriminant (b² - 4ac) qiymatiga qarab: manfiy bo'lsa haqiqiy ildiz yo'q, nol bo'lsa bitta ildiz, musbat bo'lsa ikkita ildizni chiqaring (math.sqrt dan foydalaning).

9 — String operatsiyalari

string_ops.py — bitta satr ustida quyidagi amallarni bajarib, natijalarini chop eting: uzunlik (len), katta/kichik harf (upper, lower), title, replace, split, slicing va in operatori.

10 — GitHub

$ mkdir 6-oy-dars-2
$ # fayllar
$ git add . && git commit -m "feat: dars 2 - variables and types"
$ git push

Lug'at

Termin	Izoh
int / float / str / bool	Asosiy turlar
None	Python NULL
type()	Tur tekshirish
isinstance()	Tur tekshirish (yaxshiroq)
Type conversion	int(), float(), str()
f-string	f"{name}"
Constants	SCREAMING_SNAKE_CASE
snake_case	o'zgaruvchi nomlash
math / random	Standart kutubxonalar
Truthy / Falsy	0, "", [], None — false

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