29 lines
844 B
Python
29 lines
844 B
Python
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import numpy as np
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import matplotlib.pyplot as plt
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from scipy.stats import beta
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# 定义 Beta 分布的参数
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alpha = 2
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beta_param = 2 # 注意这里变量名不能与模块名beta重复，所以用beta_param
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# 生成 x 值，Beta 分布的定义域是 [0, 1]
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# 我们生成一系列在 0 到 1 之间的点
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x = np.linspace(0.01, 0.99, 500) # 避免在0和1处logpdf可能趋向负无穷导致绘图问题，稍微避开边界
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# 计算每个 x 值的 logpdf
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log_pdf_values = beta.logpdf(x, alpha, beta_param)
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# 绘图
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plt.figure(figsize=(10, 6))
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plt.plot(x, log_pdf_values, label=f'logPDF of Beta(α={alpha}, β={beta_param})')
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# 添加标题和标签
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plt.title(f'Log-Probability Density Function (logPDF) of Beta(α={alpha}, β={beta_param})')
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plt.xlabel('x')
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plt.ylabel('log(PDF)')
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plt.grid(True)
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plt.legend()
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# 显示图形
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plt.show()
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