python加载txt数据 矩阵

def loadDataKVSet(fileName):  
    dataMat = []              
    
    fr = open(fileName,‘r‘, encoding=‘utf-8‘)
    for line in fr.readlines():
        curLine = line.strip().split(‘,‘)
        a_float = []
        for num in curLine:
            a_float.append(num)
        #fltLine = map(float, curLine)    # 将每个元素转成float类型
        dataMat.append(a_float)
        
    return dataMat