Combine Timetables and Synchronize Their Data - MATLAB & Simulink (original) (raw)
You can combine timetables and synchronize their data in a variety of ways. You can concatenate timetables vertically or horizontally, but only when they contain the same row times or timetable variables. Use the synchronize function to combine timetables with different row times and timetable variables. synchronize creates a timetable that contains all variables from all input timetables. It then synchronizes the data from the input timetables to the row times of the output timetable. synchronize can fill in missing elements of the output timetable with missing data indicators, with values copied from their nearest neighbors, or with interpolated values. synchronize also can aggregate timetable data over time bins you specify.
Concatenate Timetables Vertically
Load timetables from openPricesSmall and concatenate them vertically. The timetables are opWeek1 and opWeek2. They contain opening prices for some stocks during the first and second weeks of January 2016.
Display the two timetables.
opWeek1=5×2 timetable
Time AAPL FB
____________________ ______ ______
08-Jan-2016 09:00:00 98.55 99.88
07-Jan-2016 09:00:00 98.68 100.5
06-Jan-2016 09:00:00 100.56 101.13
05-Jan-2016 09:00:00 105.75 102.89
04-Jan-2016 09:00:00 102.61 101.95opWeek2=5×2 timetable
Time AAPL FB
____________________ ______ ______
14-Jan-2016 09:00:00 97.96 95.85
13-Jan-2016 09:00:00 100.32 100.58
12-Jan-2016 09:00:00 100.55 99
11-Jan-2016 09:00:00 98.97 97.91
08-Jan-2016 09:00:00 98.55 99.88Concatenate the timetables. You can concatenate timetables vertically when they have the same variables. The row times label the rows and are not contained in a timetable variable. Note that the row times of a timetable can be out of order and do not need to be regularly spaced. For example, op does not include days that fall on weekends. A timetable also can contain duplicate times. op contains two rows for 08-Jan-2016 09:00:00.
op=10×2 timetable
Time AAPL FB
____________________ ______ ______
14-Jan-2016 09:00:00 97.96 95.85
13-Jan-2016 09:00:00 100.32 100.58
12-Jan-2016 09:00:00 100.55 99
11-Jan-2016 09:00:00 98.97 97.91
08-Jan-2016 09:00:00 98.55 99.88
08-Jan-2016 09:00:00 98.55 99.88
07-Jan-2016 09:00:00 98.68 100.5
06-Jan-2016 09:00:00 100.56 101.13
05-Jan-2016 09:00:00 105.75 102.89
04-Jan-2016 09:00:00 102.61 101.95Concatenate Timetables Horizontally
You also can concatenate timetables horizontally. The timetables must have the same row times and different variables.
Display the timetable opOtherStocks. The timetable has the same row times as opWeek1, but variables for different stocks.
opOtherStocks=5×2 timetable Time MSFT TWTR ____________________ _____ _____
08-Jan-2016 09:00:00 52.37 20.51
07-Jan-2016 09:00:00 52.7 21
06-Jan-2016 09:00:00 54.32 21.62
05-Jan-2016 09:00:00 54.93 22.79
04-Jan-2016 09:00:00 54.32 22.64Concatenate opWeek1 and opOtherStock. The output timetable has one set of row times and the variables from both timetables.
op = [opWeek1 opOtherStocks]
op=5×4 timetable Time AAPL FB MSFT TWTR ____________________ ______ ______ _____ _____
08-Jan-2016 09:00:00 98.55 99.88 52.37 20.51
07-Jan-2016 09:00:00 98.68 100.5 52.7 21
06-Jan-2016 09:00:00 100.56 101.13 54.32 21.62
05-Jan-2016 09:00:00 105.75 102.89 54.93 22.79
04-Jan-2016 09:00:00 102.61 101.95 54.32 22.64Synchronize Timetables and Indicate Missing Data
Load air quality data and weather measurements from two different timetables and synchronize them. The dates of the measurements range from November 15, 2015, to November 19, 2015. The air quality data come from a sensor inside a building, while the weather measurements come from sensors outside.
load indoors load outdoors
Display the first five lines of each timetable. They contain measurements of different quantities taken at different times.
ans=5×2 timetable Time Humidity AirQuality ___________________ ________ __________
2015-11-15 00:00:24 36 80
2015-11-15 01:13:35 36 80
2015-11-15 02:26:47 37 79
2015-11-15 03:39:59 37 82
2015-11-15 04:53:11 36 80 ans=5×3 timetable Time Humidity TemperatureF PressureHg ___________________ ________ ____________ __________
2015-11-15 00:00:24 49 51.3 29.61
2015-11-15 01:30:24 48.9 51.5 29.61
2015-11-15 03:00:24 48.9 51.5 29.61
2015-11-15 04:30:24 48.8 51.5 29.61
2015-11-15 06:00:24 48.7 51.5 29.6 Synchronize the timetables. The output timetable tt contains all the times from both timetables. synchronize puts a missing data indicator where there are no data values to place in tt. When both input timetables have a variable with the same name, such as Humidity, synchronize renames both variables and adds both to the output timetable.
tt = synchronize(indoors,outdoors); tt(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:24 36 80 49 51.3 29.61
2015-11-15 01:13:35 36 80 NaN NaN NaN
2015-11-15 01:30:24 NaN NaN 48.9 51.5 29.61
2015-11-15 02:26:47 37 79 NaN NaN NaN
2015-11-15 03:00:24 NaN NaN 48.9 51.5 29.61 Synchronize and Interpolate Data Values
Synchronize the timetables, and fill in missing timetable elements with linear interpolation. To synchronize on a time vector that includes all times from both timetables, specify "union" for the output times.
ttLinear = synchronize(indoors,outdoors,"union","linear"); ttLinear(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:24 36 80 49 51.3 29.61
2015-11-15 01:13:35 36 80 48.919 51.463 29.61
2015-11-15 01:30:24 36.23 79.77 48.9 51.5 29.61
2015-11-15 02:26:47 37 79 48.9 51.5 29.61
2015-11-15 03:00:24 37 80.378 48.9 51.5 29.61 Synchronize to Regular Times
Synchronize the timetables to an hourly time vector. The input timetables had irregular row times. The output timetable has regular row times with one hour as the time step.
ttHourly = synchronize(indoors,outdoors,"hourly","linear"); ttHourly(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:00 36 80 49 51.299 29.61
2015-11-15 01:00:00 36 80 48.934 51.432 29.61
2015-11-15 02:00:00 36.634 79.366 48.9 51.5 29.61
2015-11-15 03:00:00 37 80.361 48.9 51.5 29.61
2015-11-15 04:00:00 36.727 81.453 48.834 51.5 29.61 Synchronize the timetables to a 30-minute time step. Specify a regular time step using the "regular" input argument and the TimeStep name-value argument.
ttHalfHour = synchronize(indoors,outdoors,"regular","linear",TimeStep=minutes(30)); ttHalfHour(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:00 36 80 49 51.299 29.61
2015-11-15 00:30:00 36 80 48.967 51.366 29.61
2015-11-15 01:00:00 36 80 48.934 51.432 29.61
2015-11-15 01:30:00 36.224 79.776 48.9 51.499 29.61
2015-11-15 02:00:00 36.634 79.366 48.9 51.5 29.61 As an alternative, you can synchronize the timetables to a time vector that specifies half-hour intervals.
tv = [datetime(2015,11,15):minutes(30):datetime(2015,11,18)]; tv.Format = indoors.Time.Format; ttHalfHour = synchronize(indoors,outdoors,tv,"linear"); ttHalfHour(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:00 36 80 49 51.299 29.61
2015-11-15 00:30:00 36 80 48.967 51.366 29.61
2015-11-15 01:00:00 36 80 48.934 51.432 29.61
2015-11-15 01:30:00 36.224 79.776 48.9 51.499 29.61
2015-11-15 02:00:00 36.634 79.366 48.9 51.5 29.61 Synchronize and Aggregate Data Values
Synchronize the timetables and calculate the daily means for all variables in the output timetable.
ttDaily = synchronize(indoors,outdoors,"daily","mean"); ttDaily
ttDaily=4×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:00 36.5 80.05 48.931 51.394 29.607
2015-11-16 00:00:00 36.85 80.35 47.924 51.571 29.611
2015-11-17 00:00:00 36.85 79.45 48.45 51.238 29.613
2015-11-18 00:00:00 NaN NaN 49.5 50.8 29.61 Synchronize the timetables to six-hour time intervals and calculate a mean for each interval.
tt6Hours = synchronize(indoors,outdoors,"regular","mean",TimeStep=hours(6)); tt6Hours(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:00 36.4 80.2 48.9 51.45 29.61
2015-11-15 06:00:00 36.4 79.8 48.9 51.45 29.6
2015-11-15 12:00:00 36.6 80.4 49.025 51.45 29.61
2015-11-15 18:00:00 36.6 79.8 48.9 51.225 29.607
2015-11-16 00:00:00 36.6 80.2 48.5 51.4 29.61 As an alternative, specify a time vector that has the same six-hour time intervals.
tv = [datetime(2015,11,15):hours(6):datetime(2015,11,18)]; tv.Format = indoors.Time.Format; tt6Hours = synchronize(indoors,outdoors,tv,"mean"); tt6Hours(1:5,:)
ans=5×5 timetable Time Humidity_indoors AirQuality Humidity_outdoors TemperatureF PressureHg ___________________ ________________ __________ _________________ ____________ __________
2015-11-15 00:00:00 36.4 80.2 48.9 51.45 29.61
2015-11-15 06:00:00 36.4 79.8 48.9 51.45 29.6
2015-11-15 12:00:00 36.6 80.4 49.025 51.45 29.61
2015-11-15 18:00:00 36.6 79.8 48.9 51.225 29.607
2015-11-16 00:00:00 36.6 80.2 48.5 51.4 29.61 See Also
timetable | table2timetable | synchronize | retime
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