基于python的数学建模---多模糊评价



权重 ak的确定——频数统计法

选取正整数p的方法
画箱形图 取1/4与3/4的距离(IQR) ceil()取整
代码:
import numpy as np
def frequency(matrix,p):
'''
频数统计法确定权重
:param matrix: 因素矩阵
:param p: 分组数
:return: 权重向量
'''
A = np.zeros((matrix.shape[0]))
for i in range(0, matrix.shape[0]):
## 根据频率确定频数区间列表
row = list(matrix[i, :])
maximum = max(row)
minimum = min(row)
gap = (maximum - minimum) / p
row.sort()
group = []
item = minimum
while(item < maximum):
group.append([item, item + gap])
item = item + gap
print(group)
# 初始化一个数据字典,便于记录频数
dataDict = {}
for k in range(0, len(group)):
dataDict[str(k)] = 0
# 判断本行的每个元素在哪个区间内,并记录频数
for j in range(0, matrix.shape[1]):
for k in range(0, len(group)):
if(matrix[k, j] >= group[k][0]):
dataDict[str(k)] = dataDict[str(k)] + 1
break
print(dataDict)
# 取出最大频数对应的key,并以此为索引求组中值
index = int(max(dataDict,key=dataDict.get))
mid = (group[index][0] + group[index][1]) / 2
print(mid)
A[i] = mid
A = A / sum(A[:]) # 归一化
return A
权重 ak的确定——模糊层次分析法

代码:
import numpy as np
def AHP(matrix):
if isConsist(matrix):
lam, x = np.linalg.eig(matrix)
return x[0] / sum(x[0][:])
else:
print("一致性检验未通过")
return None
def isConsist(matrix):
'''
:param matrix: 成对比较矩阵
:return: 通过一致性检验则返回true,否则返回false
'''
n = np.shape(matrix)[0]
a, b = np.linalg.eig(matrix)
maxlam = a[0].real
CI = (maxlam - n) / (n - 1)
RI = [0, 0, 0.58, 0.9, 1.12, 1.24, 1.32, 1.41, 1.45]
CR = CI / RI[n - 1]
if CR < 0.1:
return True, CI, RI[n - 1]
else:
return False, None, None

import numpy as np def appraise(criterionMatrix, targetMatrixs, relationMatrixs): ''' :param criterionMatrix: 准则层权重矩阵 :param targetMatrix: 指标层权重矩阵列表 :param relationMatrixs: 关系矩阵列表 :return: ''' R = np.zeros((criterionMatrix.shape[1], relationMatrixs[0].shape[1])) for index in range(0, len(targetMatrixs)): row = mul_mymin_operator(targetMatrixs[index], relationMatrixs[index]) R[index] = row B = mul_mymin_operator(criterionMatrix, R) return B / sum(B[:]) def mul_mymin_operator(A, R): B = np.zeros(1, R.shape[1]) for column in range(1, R.shape[1]): list = [] for row in range(1, R.shape[0]): list = list.append(A[row] * R[row, column]) B[0, column] = mymin(list) return B def mymin(list): global temp for index in range(1, len(list)): if index == 1: temp = min(1, list[0] + list[1]) else: temp = min(1, temp + list[index]) return temp

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