Embedded Systems LM5p-GSM, Руководство по эксплуатации продукта

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dates = {
['start'] = { year = 2016, month = 4, day = 15 },
['end'] = { year = 2016, month = 4, day = 16 },
}
-- fetch current value
day = trends.fetchone('Gas', dates)
-- get data for the past year
dates = {}
dates['start'] = os.date('*t')
dates['start'].year = dates['start'].year - 1
dates['end'] = os.date('*t')
-- fetch previous value
yearly = trends.fetch('Gas', dates, 86400)

trends.NaN value is used for points which contain invalid values or cannot be found.
The default value is 0, but it can also be set to 0 / 0 (NaN - not a number).
Example:
require('trends')
-- use "not a number" for invalid values
trends.NaN = 0 / 0
-- get data for the past year
dates = {}
dates['start'] = os.date('*t')
dates['start'].year = dates['start'].year - 1
dates['end'] = os.date('*t')
value = trends.fetchone('Hot Water', dates)
-- NaN ~= NaN, means value was not found
if value ~= value then
return
end
6.7. Scenes
Scenes section allows creating scenes visually (without using event-based scripting).
Add scene