Python Introduction

Python is a programming language that lets you work more quickly and integrate your systems more effectively.

calculator (計算機)

2 + 2 
4
2 + 2 
2 - 2
2 * 3
4 / 2 
2.0

Sample Code

The sample code in colab Python Introduction.ipynb

Output (輸出)

print() function (函式)

print(*objects, sep=' ', end='\n', file=sys.stdout, flush=False)

*objects : print content can be nothing or
           multiple things seprated by ,
sep=''   : seperate charachter default ' ' is space
end=''   : end character default \n is new line

print() Example

print(1,2,3,4)
print()
print(1,2,3,4, sep=',')
print(1,2,3,4, end=' -- ')
print('end no')
print(1,2, sep='=', end=' ** \n')
1 2 3 4

1,2,3,4
1 2 3 4 -- end no
1=2 ** 

print() Example

print('2 + 2 = ', 2 + 2) 
print('2 - 2 = ', 2 - 2)
print('2 * 3 = ', 2 * 3)
print('4 / 2 = ', 4 / 2)
print('2 ** 3 = ', 2 ** 3)
print('5 // 2 = ', 5 // 2)
print('5 % 2 = ', 5 % 2)
2 + 2 =  4
2 - 2 =  0
2 * 3 =  6
4 / 2 =  2.0
2 ** 3 =  8
5 // 2 =  2
5 %  2 =  1

Comment (註解)

Code comments explain purpose, aiding understanding. Start with # symbol.


程式註解解釋用途,以 # 開頭。

# 我是單獨一行的註解
print(2+2) # 我是程式之後的註解
4

Adding comments

print('2 + 2  = ', 2 + 2)   # 加法
print('2 - 2  = ', 2 - 2)   # 減法
print('2 * 3  = ', 2 * 3)   # 乘法
print('4 / 2  = ', 4 / 2)   # 除法
print('2 ** 3 = ', 2 ** 3)  # 次方
print('5 // 2 = ', 5 // 2)  # 商數
print('5 % 2  = ', 5 % 2)   # 餘數
2 + 2  =  4
2 - 2  =  0
2 * 3  =  6
4 / 2  =  2.0
2 ** 3 =  8
5 // 2 =  2
5 %  2 =  1

Input (輸入)

Input() Function (函式)

input([prompt]) prompt is hint string it is option

If the prompt argument is present, it is written to standard output without a trailing newline. The function then reads a line from input, converts it to a string (stripping a trailing newline), and returns that

input() Example

# input no prompt
name = input() 
print(name)

# input with prompt
name = input("please enter your name : ") 
print("hello,", name) 
Ted
Ted
please enter your name : Ted
hello,Ted

Formatting Strings

f-string formatting

f' ... {變數名稱}' f" ... {變數名稱}"
用大括號 {變數名稱} 表示直接填入變數的值

name1 = 'Eric'
name2 = 'John'
hello_str = f'Hello {name1}, my name is {name2}'
print(hello_str)
print(f'Hi {name2}, Lovely to meet you.')
Hello Eric, my name is John
Hi John, it is nice to meet you.

f-string express

f' ... {表達式或呼叫函數} ' 用大括號 {表達式或呼叫函數},Python會求出其結果並填入字串

print(f'The Answer of 24 * 8 + 4 is {24 * 8 + 4}')
name = 'ERIC'
print(f'My name is {name} and lowercase is {name.lower()}')
import math # 載入數學模組
print(f'The PI is {math.pi}') # 取出pi
The Answer of 24 * 8 + 4 is 196
My name is ERIC and lowercase is eric
The Pi is 3.141592653589793

f-string floats

{math.pi:.3f} the number 3 of decimal places

import math # 載入數學模組
# Printing the value of Pi with 3 decimal places.
print(f'The PI is {math.pi:.3f}')

# Printing the value of Pi with 5 decimal places.
print(f'The PI is {math.pi:.5f}')
The PI is 3.142
The PI is 3.14159

f-string width and justify

print("{1:5}       is -"+f'{1:5}-')
print("{1:05}      is -"+f'{1:05}-')
print("{123:*>5}   is -"+f'{123:*>5}-')
print("{1234:*<5}  is -"+f'{1234:*<5}-')
{1:5}      is -    1-
{12:05}    is -00012-
{123:>5}   is -**123-
{1234:<5}  is -1234*-

{2:0>5}
{     2        :           0                       >                5      }
{number : fill_character jusity_to_right  width  }

Python Introdution

By wschen

Python Introdution

Discover the power of Python! This presentation introduces Python as a programming language that enhances productivity and system integration. Explore topics like calculator functions, print(), comments, user input, and string formatting through engaging examples.

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