import math
i=0
filename=''
write=''
Rline = ''

def writeFile(fileName,line):
    global filename
    global write
    global Rline

    if filename!=fileName and filename=='':
        write = open('D:/soft/apache-tomcat-7.0.47/logs/'+fileName+".log", 'a+')
        write.write(line)
    elif  filename!=fileName  and Rline!='':
        write.close()#新文件就关闭上个write的流
    else:
        write.write(line)
        filename = fileName
    Rline = line
with open('D:/soft/apache-tomcat-7.0.47/logs/cloudq.log','r') as infile:
    for line in infile:
        name = i/500#设置每一个文件500行。
        # print(math.floor(name))
        writeFile(str(math.floor(name)),line)
        i=i+1

如果代码报错，请去掉中文注释再试。