【python/ros】如何将rosbag的topic数据保存成csv/txt文件

• 记录bag包topic保存的常用方法

• 通过命令保存

  rostopic echo -b xxx.bag -p /topic_name > xxx.csv
  

• topic自动提取存储为csv

  from bagpy import bagreader
  import pandas as pd
  
  bagPath = r"/your/path/xxx.bag"
  Bag = bagreader(bagPath)	# topics = Bag.topic_table print(topics)
  
  # topic内容自动提取到/your/path/xxx(bag包名字)/路径下csv文件
  perception_topic = Bag.message_by_topic("/perception/obstacles")
  

• 使用pandas保存，这种方式有点冗余

  from bagpy import bagreader
  import pandas as pd
  
  bagPath = r"/your/path/xxx.bag"
  Bag = bagreader(bagPath)
  perception_topic = Bag.message_by_topic("/perception/obstacles")
  topicData = pd.read_csv(perception_topic)
  directory = '/your/path/'
  topicData.to_csv(directory + "perception_obstacles.csv")
  # topicData
  

• 使用csv库保存，可改写保存topic的消息字段

  import csv
  file = open('文件名.csv', 'w', encoding='utf-8')
  
  # 基于文件对象构建csv写入对象
  csv_writer = csv.writer(file)
  
  # 构建列表头
  csv_writer.writerow(["姓名","年龄","性别"])
  
  # 写入csv文件内容
  csv_writer.writerow(["alice",'21','女'])
  csv_writer.writerow(["bob",'20','男'])
  csv_writer.writerow(["clark",'22','男'])
  
  f.close()
  

• 直接使用命令保存

  rostopic echo -b xxx.bag -p /topic_name > xxx.txt
  

• open()直接创建文件对象

  object = {}
  # object赋值
  file = open('/your/path/' + 'perception_obstacles.txt', "w", encoding='utf-8')
  if object is not None:
      for target_id in object.keys():
          for values in object[target_id]:
              fields = ' '.join(map(lambda x: str(x), values))
              file.write(fields + 'n')
  file.close()
  

参考文章：
python写入数据到txt文本中
python读取bag保存到csv
rostopic命令保存csv/txt

created by shuaixio, 2022.06.04