Analyse table value for calculations

2 次查看（过去 30 天）
The Fit
The Fit 2018-2-8
回答： Peter Perkins 2018-2-12
Hi all,
i have a table with 2 cols, first is date with time and second one is with data (output). Because data in col2 is cumulating each day and they reset to 0 every midnight i looking for solution how to count yearly and monthly consume. It mean i need sum all data before they turn to zero and than sum specific month (January)
year month day hour minute second output
117 1 2 23 48 51.2680000000000 801.500000000000
117 1 2 23 51 51.3200000000000 803.500000000000
117 1 2 23 54 51.3420000000000 805.500000000000
117 1 2 23 57 51.3620000000000 1.30000000000000
117 1 3 0 0 51.4110000000000 3.70000000000000
117 1 3 0 3 52.0680000000000 5.60000000000000
i did it in excel with if function but i cant find solution for that in matlab :(..
  1 个评论
Eric Tao
Eric Tao 2018-2-9
编辑：Eric Tao 2018-2-9
I have a doubt to your table. If the col 'output' is reset to 0 every midnight, how would the output in 4th row (1.3) be smaller than the one in 3rd row (805.5)? It is supposed to be larger than 805.5 since output is cumulating and the time did not meet 00:00:00(i.e., hour == 0 & minute == 0).

请先登录，再进行评论。

请先登录，再回答此问题。

回答（2 个）

Kai Domhardt
Kai Domhardt 2018-2-9
First you will want to select the relevant subset of your data. For this example I will simply use the data of february.
feb_data = my_table.output( my_table.dates.Month == 2 );
Now you will only need to sum up the daily consumption in your subset, which is given by the maximum/last value for each day.
Since your data is shaped like a sawtooth wave, the value only decreases right after the local maximum.
feb_sum = sum( feb_data( diff(feb_data)<0 ) );
Finally, the you need to end the last datapoint of your subset to the sum, since the line above would not include it in the sum.
feb_sum = feb_sum + feb_data(end);
-----
You can also be more concise and combine the two code lines above into one:
feb_sum = sum( [feb_data( diff(feb_data)<0 ); feb_data(end)] );
Peter Perkins
Peter Perkins 2018-2-12
Like Eric, I will observe that your example seems wrong, and it's not at all clear what you are starting with and what you want to end up with.
Depending on what you have and what you want, you should be able to use either varfun or rowfun on the table.
If you have access to R2016b or later, it's likely that you want to convert your six date/time variables to a datetime vector, and create a timetable with just one variable, and then use retime. Hard to say without knowing the rest of the context.

类别

在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by