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Mosh的Python课程笔记(2)--基本类型

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Mosh的课程网址

Primitive Types

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students_count = 1000
rating = 4.99
is_published = False    # case sensitive (区分大小写)
course_name = "Python Programming"

String

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course_name = "Python Programming"
message = """
Hi John
This is Stone from China
blablabla
"""
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course_name = "Python Programming"
print(len(course_name))		# 18
print(course_name[0])		# P
print(course_name[-1])		# g
print(course_name[0:3])		# Pyt
print(course_name[0:])		# Python Programming
print(course_name[:3])		# Pyt
print(course_name[:])		# Python Programming

Escape Sequences

转义字符

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course_name = "Python \"Programming"
print(course_name) 	# Python "Programming
# \"    \'   \\   \n

Formatted Strings

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first = "Stone"
last = "Purple"
full = f"{first} {last}"
print(full)						# Stone Purple
print(f"{len(first)} {2 + 2}")	# 5 4

String Methods

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course = "  Python Programming"
print(course.upper())
print(course.lower())
print(course.title())
print(course.strip())  # lstrip, rstrip
print(course.find("Pro"))
print(course.replace("P", "J"))
print("Pro" in course)
print("swift" not in course)

输出结果：

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  PYTHON PROGRAMMING
  python programming
  Python Programming
Python Programming
9
  Jython Jrogramming
True
True

Numbers

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x = 1
x = 1.1
x = 1 + 2j  # complex number

# 	+	 -	 *	 /	 %	 //		 **
print(10 / 3)   	# 3.3333333333333335
print(10 // 3)		# 3
print(10 ** 3)		# 1000

x = 10
x = x + 3
x += 3

Working with Numbers

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import math

print(round(2.9))		# 3
print(abs(-2.9))		# 2.9

print(math.ceil(2.2))	# 3

Type Conversion

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x = input("x: ")
print(type(x))
y = int(x) + 1		# type conversion
print(f"x: {x}, y: {y}")
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x: 2
<class 'str'>
x: 2, y: 3

对于bool(x)，为 False 的情况只有：“”，0，None

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print(bool(""))			# False

Quiz

👉 What are the primitive types in Python?

👉 What are the results?

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fruit = "Apple"
print(fruit[1])
print(fruit[1:-1])

👉 What are the results?

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print(10 % 3)
print(bool("False"))