# 基本語法
name = "張三"
age = 25
print(f"姓名：{name}，年齡：{age}")

# 浮點(diǎn)數(shù)格式化
pi = 3.1415926
print(f"圓周率：{pi:.2f}")  # 保留2位小數(shù)

number = 12.3456

# 寬度控制示例
print(f"|{number:.2f}|")          # 默認(rèn)
print(f"|{number:10.2f}|")        # 寬度10
print(f"|{number:<10.2f}|")       # 左對齊
print(f"|{number:>10.2f}|")       # 右對齊
print(f"|{number:^10.2f}|")       # 居中對齊

positive = 12.34
negative = -12.34

print(f"正數(shù): {positive:+.2f}")  # +12.34
print(f"負(fù)數(shù): {negative:+.2f}")  # -12.34
print(f"正數(shù): {positive:-.2f}")  # 12.34
print(f"負(fù)數(shù): {negative:-.2f}")  # -12.34
print(f"空格: {positive: .2f}")  #  12.34

# 表達(dá)式計(jì)算
a, b = 5, 3
print(f"{a} +  = {a + b}")  # 5 + 3 = 8

# 調(diào)用函數(shù)
name = "python"
print(f"大寫: {name.upper()}")  # 大寫: PYTHON

# 字典訪問
person = {"name": "李四", "age": 30}
print(f"姓名: {person['name']}, 年齡: {person['age']}")

# 條件表達(dá)式
score = 85
print(f"成績: {score}，等級: {'優(yōu)秀' if score >= 90 else '良好' if score >= 80 else '及格'}")

# 基本用法
name = "王五"
age = 28
print("姓名：{}，年齡：{}".format(name, age))

# 位置參數(shù)
print("{0}的{1}成績是{2}分".format("小明", "數(shù)學(xué)", 95))

# 關(guān)鍵字參數(shù)
print("坐標(biāo)：({x}, {y})".format(x=10, y=20))

# 對齊和填充
print("{:*^20}".format("居中標(biāo)題"))  # ******居中標(biāo)題******

# 數(shù)字格式化
print("十進(jìn)制: {0:d}, 十六進(jìn)制: {0:x}, 八進(jìn)制: {0:o}, 二進(jìn)制: {0:b}".format(42))

# 千位分隔符
print("{:,}".format(123456789))  # 123,456,789

# 百分比
print("{:.2%}".format(0.875))  # 87.50%

# 基本用法
name = "趙六"
age = 35
print("姓名：%s，年齡：%d" % (name, age))

# 浮點(diǎn)數(shù)格式化
pi = 3.1415926
print("圓周率：%.2f" % pi)

# 千位分隔符示例
numbers = [1234, 1234567, 1234567890]

print("千位分隔符格式化:")
for num in numbers:
    print(f"{num:,}")          # f-string方式
    print("{:,}".format(num))  # format方式
    print("%d" % num)          # %方式（不支持千位分隔符）

# 科學(xué)計(jì)數(shù)法格式化
small_numbers = [0.000123, 0.001234, 0.012345]
large_numbers = [1234567, 123456789, 12345678901]

print("小數(shù)的科學(xué)計(jì)數(shù)法:")
for num in small_numbers:
    print(f"{num:.2e}")

print("\n大數(shù)的科學(xué)計(jì)數(shù)法:")
for num in large_numbers:
    print(f"{num:.2e}")

# 百分比格式化
percentages = [0.1234, 0.5678, 0.9876, 1.2345]

print("百分比格式化:")
for pct in percentages:
    print(f"{pct:.2%}")          # f-string方式
    print("{:.2%}".format(pct))  # format方式
    print("%.2f%%" % (pct * 100)) # %方式

# 四舍五入測試案例
test_cases = [
    (1.234, 2),   # 期望: 1.23
    (1.235, 2),   # 期望: 1.24
    (1.236, 2),   # 期望: 1.24
    (1.225, 2),   # 特殊情況: 1.22
    (1.245, 2),   # 1.24
    (2.675, 2),   # 2.68
    (2.665, 2),   # 2.66
]

print("四舍五入規(guī)則測試:")
for num, precision in test_cases:
    formatted = f"{num:.{precision}f}"
    print(f"{num} -> {formatted}")

def format_financial_data():
    """金融數(shù)據(jù)格式化示例"""
    
    # 股票價(jià)格數(shù)據(jù)
    stocks = [
        {"name": "AAPL", "price": 182.63, "change": 2.45, "change_percent": 1.36},
        {"name": "GOOGL", "price": 138.21, "change": -1.23, "change_percent": -0.88},
        {"name": "MSFT", "price": 337.29, "change": 5.67, "change_percent": 1.71},
    ]
    
    print("股票行情:")
    print(f"{'名稱':<8} {'價(jià)格':>10} {'漲跌':>10} {'漲幅':>10}")
    print("-" * 45)
    
    for stock in stocks:
        # 根據(jù)漲跌設(shè)置顏色標(biāo)記（實(shí)際顯示可能需要支持ANSI顏色的終端）
        change_color = "+" if stock["change"] >= 0 else ""
        percent_color = "+" if stock["change_percent"] >= 0 else ""
        
        print(f"{stock['name']:<8} "
              f"${stock['price']:>9.2f} "
              f"{change_color}{stock['change']:>9.2f} "
              f"{percent_color}{stock['change_percent']:>9.2f}%")

def format_currency(amount, currency="CNY"):
    """貨幣金額格式化"""
    symbols = {
        "CNY": "￥",
        "USD": "$",
        "EUR": "€",
        "GBP": "￡",
        "JPY": "￥"
    }
    
    symbol = symbols.get(currency, currency)
    return f"{symbol}{amount:,.2f}"

# 使用示例
format_financial_data()

print("\n貨幣格式化示例:")
amounts = [1234.56, 7890.12, 45678.90, 123456.78]
for amount in amounts:
    print(f"人民幣: {format_currency(amount)}, "
          f"美元: {format_currency(amount, 'USD')}")

def format_scientific_report():
    """科學(xué)數(shù)據(jù)報(bào)告格式化"""
    
    # 實(shí)驗(yàn)數(shù)據(jù)
    experiments = [
        {"name": "實(shí)驗(yàn)A", "value": 0.000123456, "uncertainty": 0.000000123},
        {"name": "實(shí)驗(yàn)B", "value": 1234.56789, "uncertainty": 12.34567},
        {"name": "實(shí)驗(yàn)C", "value": 9876543.21, "uncertainty": 9876.543},
    ]
    
    print("科學(xué)實(shí)驗(yàn)數(shù)據(jù)報(bào)告:")
    print(f"{'實(shí)驗(yàn)名稱':<12} {'測量值':>15} {'不確定度':>15} {'相對誤差':>12}")
    print("-" * 60)
    
    for exp in experiments:
        # 根據(jù)數(shù)值大小選擇合適的格式
        if abs(exp["value"]) < 0.001 or abs(exp["value"]) > 1000000:
            value_str = f"{exp['value']:.3e}"
            uncertainty_str = f"{exp['uncertainty']:.3e}"
        else:
            value_str = f"{exp['value']:,.3f}"
            uncertainty_str = f"{exp['uncertainty']:,.3f}"
        
        # 計(jì)算相對誤差
        relative_error = abs(exp["uncertainty"] / exp["value"]) * 100
        
        print(f"{exp['name']:<12} {value_str:>15} {uncertainty_str:>15} {relative_error:>11.2f}%")

def format_chemical_concentration(concentration, unit="mol/L"):
    """化學(xué)濃度格式化"""
    if concentration < 0.000001:
        return f"{concentration:.2e} {unit}"
    elif concentration < 0.001:
        return f"{concentration * 1000000:.2f} μ{unit}"
    elif concentration < 1:
        return f"{concentration * 1000:.2f} m{unit}"
    else:
        return f"{concentration:.2f} {unit}"

# 使用示例
format_scientific_report()

print("\n化學(xué)濃度格式化示例:")
concentrations = [0.000000123, 0.000456, 0.789, 12.345]
for conc in concentrations:
    print(f"濃度: {format_chemical_concentration(conc)}")

def generate_data_table():
    """生成格式化的數(shù)據(jù)表格"""
    
    # 學(xué)生成績數(shù)據(jù)
    students = [
        {"name": "張三", "math": 95.5, "english": 88.0, "science": 92.3, "history": 85.7},
        {"name": "李四", "math": 87.2, "english": 91.5, "science": 89.8, "history": 93.1},
        {"name": "王五", "math": 78.9, "english": 82.4, "science": 76.5, "history": 79.8},
        {"name": "趙六", "math": 92.1, "english": 94.7, "science": 96.3, "history": 90.2},
    ]
    
    # 表頭
    headers = ["姓名", "數(shù)學(xué)", "英語", "科學(xué)", "歷史", "平均分", "等級"]
    
    print("學(xué)生成績表")
    print("=" * 70)
    
    # 打印表頭
    header_line = " | ".join(f"{header:^8}" for header in headers)
    print(f"| {header_line} |")
    print("|" + "-" * 70 + "|")
    
    # 打印數(shù)據(jù)行
    for student in students:
        # 計(jì)算平均分
        scores = [student["math"], student["english"], student["science"], student["history"]]
        average = sum(scores) / len(scores)
        
        # 確定等級
        if average >= 90:
            grade = "優(yōu)秀"
        elif average >= 80:
            grade = "良好"
        elif average >= 70:
            grade = "中等"
        elif average >= 60:
            grade = "及格"
        else:
            grade = "不及格"
        
        # 格式化輸出
        name = f"{student['name']:^8}"
        math = f"{student['math']:>7.1f}"
        english = f"{student['english']:>7.1f}"
        science = f"{student['science']:>7.1f}"
        history = f"{student['history']:>7.1f}"
        avg = f"{average:>7.1f}"
        grade_str = f"{grade:^8}"
        
        data_line = " | ".join([name, math, english, science, history, avg, grade_str])
        print(f"| {data_line} |")
    
    print("=" * 70)

# 生成表格
generate_data_table()

import timeit

def performance_comparison():
    """各種格式化方法性能比較"""
    
    # 測試數(shù)據(jù)
    name = "測試用戶"
    value = 1234.56789
    count = 10000
    
    # f-string性能測試
    f_string_time = timeit.timeit(
        lambda: f"姓名：{name}，數(shù)值：{value:.2f}",
        number=count
    )
    
    # format()性能測試
    format_time = timeit.timeit(
        lambda: "姓名：{}，數(shù)值：{:.2f}".format(name, value),
        number=count
    )
    
    # %操作符性能測試
    percent_time = timeit.timeit(
        lambda: "姓名：%s，數(shù)值：%.2f" % (name, value),
        number=count
    )
    
    print("格式化方法性能比較（執(zhí)行{}次）:".format(count))
    print(f"f-string:  {f_string_time:.5f}秒")
    print(f"format():  {format_time:.5f}秒")
    print(f"%操作符:   {percent_time:.5f}秒")

# 運(yùn)行性能測試
performance_comparison()

class FinancialReport:
    """財(cái)務(wù)報(bào)表生成器"""
    
    def __init__(self, company_name, currency="CNY"):
        self.company_name = company_name
        self.currency = currency
        self.data = []
    
    def add_record(self, category, q1, q2, q3, q4):
        """添加季度數(shù)據(jù)記錄"""
        self.data.append({
            "category": category,
            "q1": q1, "q2": q2, "q3": q3, "q4": q4,
            "total": q1 + q2 + q3 + q4,
            "average": (q1 + q2 + q3 + q4) / 4
        })
    
    def format_currency(self, amount):
        """格式化貨幣金額"""
        symbols = {"CNY": "￥", "USD": "$", "EUR": "€", "GBP": "￡"}
        symbol = symbols.get(self.currency, self.currency)
        return f"{symbol}{amount:,.2f}"
    
    def generate_report(self):
        """生成格式化報(bào)表"""
        
        print(f"\n{'='*80}")
        print(f"{self.company_name} - 年度財(cái)務(wù)報(bào)表".center(80))
        print(f"{'='*80}")
        
        # 表頭
        headers = ["項(xiàng)目", "第一季度", "第二季度", "第三季度", "第四季度", "年度總計(jì)", "季度平均"]
        header_line = " | ".join(f"{header:^12}" for header in headers)
        print(f"| {header_line} |")
        print(f"|{'='*80}|")
        
        # 數(shù)據(jù)行
        grand_total = 0
        for record in self.data:
            category = f"{record['category']:<12}"
            q1 = f"{self.format_currency(record['q1']):>12}"
            q2 = f"{self.format_currency(record['q2']):>12}"
            q3 = f"{self.format_currency(record['q3']):>12}"
            q4 = f"{self.format_currency(record['q4']):>12}"
            total = f"{self.format_currency(record['total']):>12}"
            average = f"{self.format_currency(record['average']):>12}"
            
            data_line = " | ".join([category, q1, q2, q3, q4, total, average])
            print(f"| {data_line} |")
            
            grand_total += record['total']
        
        print(f"|{'='*80}|")
        
        # 總計(jì)行
        print(f"| {'年度總計(jì)':<12} | {'':>12} | {'':>12} | {'':>12} | {'':>12} | "
              f"{self.format_currency(grand_total):>12} | {'':>12} |")
        print(f"{'='*80}")

# 使用示例
report = FinancialReport("某科技有限公司", "CNY")
report.add_record("營業(yè)收入", 1250000, 1380000, 1520000, 1680000)
report.add_record("營業(yè)成本", 750000, 820000, 890000, 950000)
report.add_record("毛利潤", 500000, 560000, 630000, 730000)
report.add_record("凈利潤", 250000, 280000, 315000, 365000)

report.generate_report()

# 快速參考卡片
def formatting_quick_reference():
    """格式化快速參考"""
    
    examples = [
        ("基本精度", "f'{3.1415926:.2f}'", "3.14"),
        ("寬度對齊", "f'{12.3456:10.2f}'", "     12.35"),
        ("符號顯示", "f'{12.34:+.2f}'", "+12.34"),
        ("千位分隔", "f'{1234567:,.2f}'", "1,234,567.00"),
        ("科學(xué)計(jì)數(shù)", "f'{0.000123456:.2e}'", "1.23e-04"),
        ("百分比", "f'{0.875:.2%}'", "87.50%"),
    ]
    
    print("Python字符串格式化快速參考")
    print("=" * 60)
    for desc, code, result in examples:
        print(f"{desc:12} {code:30} → {result}")
    print("=" * 60)

# 顯示快速參考
formatting_quick_reference()