使用 Matlab 重新格式化传感器数据

Question

I have a lot of sensor data sorted into 3 columns, time, sensor name, and sensor value. Wherein sensor name repeats every row, until it gets to the next sensor.

For example: https://i.stack.imgur.com/H9KKi.png (can't post, not enough rep on this stack exchange)

I want to reformat the data into separate column variables, lined up with their time stamps. What would be the best way to do this? Preferably using Matlab, Excel, or origin. So column headers of time, sensorA, sensorB, with their values underneath.

Many thanks.

Answer 1

I recommend using the unstack command. In the below I read data into a table and then convert to a more tabular form.

d = readtable("sensorData.xlsx")
d1 = unstack(d,"Value","Sensor")

d =

  15×3 table

            Date              Sensor      Value
    ____________________    __________    _____

    12-May-2020 13:00:00    {'Sens_a'}     64  
    12-May-2020 14:00:00    {'Sens_a'}      9  
    12-May-2020 14:59:59    {'Sens_a'}     70  
    12-May-2020 15:59:59    {'Sens_a'}     74  
    12-May-2020 13:00:00    {'Sens_b'}     37  
    12-May-2020 14:00:00    {'Sens_b'}     63  
    12-May-2020 14:59:59    {'Sens_b'}     47  
    12-May-2020 15:59:59    {'Sens_b'}     94  
    12-May-2020 16:59:59    {'Sens_b'}     35  
    12-May-2020 17:59:59    {'Sens_b'}     86  
    12-May-2020 18:59:59    {'Sens_b'}     26  
    12-May-2020 13:00:00    {'Sens_c'}     91  
    12-May-2020 14:00:00    {'Sens_c'}      4  
    12-May-2020 14:59:59    {'Sens_D'}     22  
    12-May-2020 15:59:59    {'Sens_D'}     74  


d1 =

  7×5 table

            Date            Sens_D    Sens_a    Sens_b    Sens_c
    ____________________    ______    ______    ______    ______

    12-May-2020 13:00:00     NaN        64        37        91  
    12-May-2020 14:00:00     NaN         9        63         4  
    12-May-2020 14:59:59      22        70        47       NaN  
    12-May-2020 15:59:59      74        74        94       NaN  
    12-May-2020 16:59:59     NaN       NaN        35       NaN  
    12-May-2020 17:59:59     NaN       NaN        86       NaN  
    12-May-2020 18:59:59     NaN       NaN        26       NaN  

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