AI-Learning

# sample.txt
# ---
# Python Programming
# File Handling
# ---
with open('sample.txt', 'r') as f:
print(f.read(7))
print(f.readline())

$ python -m venv env
$ source env/bin/activate

a, b = 5, None
result = "成立" if a > 0 or b is not None else "不成立"
print(result)

$ python -m venv env
$ source env/bin/activate
$ deactivate
$ which python

# sample.txt は存在しない
try:
with open('sample.txt', 'r+') as f:
f.write("Hello, World!")
except FileNotFoundError:
print("File not found")

a, b = 0, -1
result = "条件を満たす" if a or b < 0 else "条件を満たさない"
print(result)

value = 255
formatted = "{:X}".format(value)
print(formatted)

x = 0
result = "ゼロ以外" if x or x + 5 else "ゼロです"
print(result)

# sample.txt
# ---
# Line1
# Line2
# ---
with open('sample.txt', 'r') as f:
print(f.read())
print(f.read())

# sample.txt
# ---
# Line1
# Line2
# ---
with open('sample.txt', 'r') as f:
for line in f:
print(line.strip())

$ python -m venv env
$ source env/bin/activate
$ pip freeze > requirements.txt
$ cat requirements.txt

# sample.txt
# ---
# Python is fun.
# Let's learn it!
# ---
with open('sample.txt', 'r') as f:
lines = f.???
print(lines)

# ファイル名: sample.txt
with open('sample.txt', 'w') as f:
f.write("First Line\n")
f.flush()
f.write("Second Line\n")

value = ""
result = "空でない値です" if bool(value) else "空の値です"
print(result)

$ python -m venv myenv
$ source myenv/bin/activate
$ which python

values = [1.2345, 2.3456, 3.4567]
formatted = ["{:.1f}".format(v) for v in values]
result = ", ".join(formatted)
print(result)

# sample.txt の初期内容:
# ---
# Old Content
# ---
with open('sample.txt', 'w') as f:
f.write("New Content")

value = 0.98765
formatted = "{:.3e}".format(value)
print(formatted)

items = [None, 0, "", False]
result = "有効な要素が含まれていません" if not any(items) else "有効な要素が含まれています"
print(result)

# sample.txt
# ---
# Line1
# Line2
# ---
with open('sample.txt', 'r') as f:
lines = f.readlines()
print(len(lines))

# sample.txt
# ---
# Python is amazing!
# ---
with open('sample.txt') as f:
print(f.read(6))

# sample.txt
# ---
# Initial Line
# ---
with open('sample.txt', 'a+') as f:
f.write("\nAppended Line")
f.seek(0)
print(f.read())

# ファイル名: sample.txt
# 初期内容:
# ---
# Line1
# Line2
# ---
with open('sample.txt', 'r+') as f:
f.write("New")
f.seek(6)
f.write("Content")

n = 10
result = "偶数かつ5の倍数" if n % 2 == 0 and n % 5 == 0 else "条件を満たさない"
print(result)

try:
with open('missing.txt', 'r') as f:
data = f.read()
except ??? as e:
print(f"Error: {e}")

# sample.txt
# ---
# Hello, Python!
# ---
with open('sample.txt', 'r') as f:
for line in f:
print(line, end="")

data = {"name": "Alice", "age": 25, "score": 92.5}
formatted = "{name} is {age} years old and scored {score:.1f}.".format(**data)
print(formatted)

x, y = 5, 10
result = "条件成立" if x 5 else "条件不成立"
print(result)

username = None
result = "ユーザー名が設定されています" if username else "ユーザー名が設定されていません"
print(result)

value = 0.1234
formatted = "{:.2%}".format(value)
print(formatted)

value = []
result = "空のリストです" if not value else "リストに値があります"
print(result)

# sample.txt は存在しない
try:
with open('sample.txt', 'w+') as f:
f.write("Testing w+ mode")
f.seek(0)
print(f.read())
except Exception as e:
print(f"Error: {e}")