有一个测量程序，采集两路信号，每1s采集一次，要求每采集一次，就将采集结果写入文本文件尾部，即使重新运行程序，仍能保证数据添加到文件尾部，而不会覆盖原有数据。格式为a保留4位小数，b为整数，如右图所示。-There is a measurement program, collecting two signals, collected once every 1s, which require each collection time, the results will be collected to write a text file tail, even if re-run the program, can still ensure that the data added to the end of the file, without overwriting the original data. Format is a 4 places of decimal, b is an integer, as shown.