从Python到MATLAB的实时数据传输

时间:2014-07-30 00:30:40

标签: python matlab scipy

我正在使用python从USB输入设备读取数据。我想知道是否有一种方法可以在MATLAB中实时交换模型。我现在该怎么做是将读取的数据保存在.mat文件中,然后让模型从那里读取它,这不是很直观。我用的代码如下:

    #Import the needed libraries
    import usb.core,usb.util,sys,time
    import sys
    from array import *
    import scipy.io

    #find our device
    dev = usb.core.find(idVendor=0x046d, idProduct=0xc29a)

    # was it found?
    if dev is None:
       raise ValueError('Device not found')

   # set the active configuration. With no arguments, the first
   # configuration will be the active one
   try:
     dev.set_configuration()
     #In the event of an error
   except usb.core.USBError as e:
     print('Cannot set configuration the device: %s' %str(e))
     sys.exit()

   # get an endpoint instance
   cfg = dev.get_active_configuration()
   intf = cfg[(0,0)]
   ep = usb.util.find_descriptor(
               intf,
     # match the first IN endpoint
     custom_match = \
     lambda e: \
     usb.util.endpoint_direction(e.bEndpointAddress) == \
     usb.util.ENDPOINT_IN)

  #Initialising variables
  #Databases for access in MATLAB
  gas_pedal_data={}
  brake_pedal_data={}
  steering_wheel_bit5_data={}
  steering_wheel_bit6_data={}
  gas_pedal=[]
  brake_pedal=[]
  steering_wheel_bit5=[]
  steering_wheel_bit6=[]
  i=0
  #Read data from the device as long as it is connected
  while(dev!= None):
       try:
          #Read data
          data = dev.read(ep.bEndpointAddress, ep.wMaxPacketSize,
                          timeout=1000)
          gas_pedal.append(data[6])
          gas_pedal_data['gas_pedal']=gas_pedal
          scipy.io.savemat('test.mat',gas_pedal_data)
          brake_pedal.append(data[7])
          brake_pedal_data['brake_pedal']=brake_pedal
          scipy.io.savemat('test.mat',brake_pedal_data)
          steering_wheel_bit5.append(data[4])
          steering_wheel_bit5_data['steering_wheel_bit5']=steering_wheel_bit5
          scipy.io.savemat('test.mat',steering_wheel_bit5_data)
          steering_wheel_bit6.append(data[5])
          steering_wheel_bit6_data['steering_wheel_bit6']=steering_wheel_bit6
          scipy.io.savemat('test.mat',steering_wheel_bit6_data)
       except usb.core.USBError as e:
          print("Error readin data: %s" %str(e))
          time.sleep(5)
          continue

1 个答案:

答案 0 :(得分:0)

您有几个选择。

  • 您可以在Matlab内部查看是否存在文件,然后在可用时读取新数据
  • 您可以打开一个管道来执行python和matlab之间的进程间通信(还需要从matlab端进行轮询)。有关代码,请参阅here
  • 您可以使用本地UDP或TCP套接字进行通信。使用PNET(仍需要轮询)或matlab仪器控制工具箱(允许您配置回调函数)。

由于matlab是单线程的,因此您的模型必须考虑到提供新数据。您需要明确触发模型,以便在提供新数据时重新评估。