python拆分CANLog

通过CANOE 导出的log通常有很多个ID的数据，如何才能找到某一个ID下的特殊的信号？利用python可以简单的进行这个步骤，代码如下：

说明：

　　最终的效果是将log信息，分不同的ID进行拆分，并单独生成文件log_id.csv的文件夹。

　　1. 需要输入输入文件夹

　　2. 生成_out文件夹。

　　3. 没有错误处理

　　4. 采用"[A-F|\d]{3}"匹配CAN ID

 #log analy about CAN Signal for CANOE
 import os
 import re

 ID_Info = {}
 fold_in = input("Please input Folder In:")
 fold_out = fold_in + "_out"
 os.mkdir(fold_out)
 rep_id = r"[A-F|\d]{3}"
 patt_id = re.compile(rep_id)
 def Info_Report():
   '''
   CAN Log中的信息有固定的位数。
     0：时间戳
     1：1/2
     2：ID
     3：Rx/Tx
     4: d
     5: data Length
     6: data length number info
   '''
   pass

 def Dev_Folder(folder_in):
   for fi in os.listdir(folder_in):
     #打开文件
     with open(os.path.join(folder_in,fi),"r") as file:
       #遍历文件行
       for line in file:
         #拆分文件，去掉空格，去掉前后逗号
         a = re.sub('\s+',',',line).strip(",")
         #判断List是否有3个以上的元素，并且第3个是否为ID.
         if len(a.split(",")) > 2 and patt_id.match(a.split(",")[2]):
           if a.split(",")[2] in ID_Info.keys():
             #如果在字典中，直接将信息写入到该文件中
             pass
           else:
           #新建一个文件，关联字典
             ID_Info[a.split(",")[2]] = open((os.path.join(fold_out + "\\" + "Log_" + a.split(",")[2]) + ".csv"),"w")
           ID_Info[a.split(",")[2]].write(a+"\n")
           #print(a.split(",")[0])
   for key in ID_Info:
     ID_Info[key].close()

 if __name__ == '__main__':
   Dev_Folder(fold_in)
       

以上拆分为单个的ID了，那么如何找到某一个信号的值呢？可以通过下面的代码进行计算：

 '''
 CANOE Log
 '''
 '''

 '''
 start_bit = 0
 data_length = 0
 can_mode = 0

 def Info_Report():
   '''
   Need Input This information about CAN setting.
   start bit: start_bit
   Length   : Data_Length
   start bit mode : LSB(0)/MSB(1)
   default:LSB(0)
   '''
   pass

 def SetBit(start,length,mode = 0):
   '''
   for Get Info or set info
   '''
   start_bit = start
   data_length = length
   can_mode = mode

 def Analyse_ID_File(File_Input_Name,File_Output_Name):
   '''
   Analyse id for Every ID Signal
   '''
   #open file
   file_out = open(File_Output_Name,"w")
   with open(File_Input_Name,"r") as file:
     for line in file:
       #拆分每一行,放入到list中
       data_list = line.split(",")
       data_length = int(data_list[5],16)
       list_in = data_list[6:6+data_length]
       data_signal = Find_FromList(list_in)
       file_out.write(data_list[0]+","+str(data_signal)+"\n")
   file_out.close()

 def Find_FromList(data_list):
   dataMerge = ''
   a,b,c = Find_StartEnd(start_bit,data_length,can_mode)
   #print(data_list)
   if len(data_list) > b:
     for i in range(a,b+1):
       #print(i)
       dataMerge = dataMerge + data_list[i]
       #print(dataMerge)
     data_Digit = (int(dataMerge,16)>>c) & ((1<<(data_length))-1)
     return (data_Digit)
     #print(dataMerge)

 def Find_StartEnd(start,length,mode):
   '''
   This Function return value:
   byte_little,byte_big,bigbyte_bit
   '''
   startbyte = start >> 3
   startbit = start % 8
   if mode == 0:
     litByte = startbyte - ((startbit+length-1)>>3)
     BigByte = startbyte
     Endbit = startbit
   else:
     pass
   return (litByte,BigByte,Endbit)

 if __name__ == '__main__':
   #print(Find_StartEnd(32,20,1))
   file_name = input("Please input file You need Analyse:")
   file_out_name = input("Please input file You need Out(.csv):")
   start_bit,data_length,can_mode = map(int,input("please input can info(start_bit,data_length,can_mode(0/1),PV为0):").split(","))
   Analyse_ID_File(file_name,file_out_name)

以上，如果不通过导入每个信号信息含义的话，是可以快速的找到某个信号在整个log中的值得变化的。

　　以上，只支持以LSB开始，计算长度的算法。如果以MSB需要在''Find_StartEnd"函数中增加''mode == 1''的处理。