36 lines
855 B
Python
36 lines
855 B
Python
import numpy as np
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from scipy.special import gammaln # gammaln(x) 计算 ln(x!) 更为高效
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def andromeda_score(k, n, p=0.06):
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"""
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计算Andromeda算法的得分。
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参数:
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- k: 匹配的理论峰数
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- n: 理论峰的总数
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- p: 匹配概率，默认0.06
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返回:
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- Andromeda得分
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"""
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# 计算匹配项和不匹配项
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match_term = -k * np.log(p)
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non_match_term = -(n - k) * np.log(1 - p)
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# 计算组合项
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factln_n = gammaln(n + 1) # 对应 Factln(n)
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factln_k = gammaln(k + 1) # 对应 Factln(k)
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factln_n_k = gammaln(n - k + 1) # 对应 Factln(n - k)
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# Andromeda得分
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score = match_term + non_match_term - factln_n + factln_k + factln_n_k
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# 缩放得分
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score = 10.0 * score / np.log(10)
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return score
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# 示例计算
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k = 2
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n = 5
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andromeda_score(k, n)
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