(04.12.2018, 13:45)merel Wrote: Hello.

You can try this:

Code:

function linear_by_table(input,curve,offset)
local FDY = offset or 0
    fk1= (curve["y"][1] - curve["y"][2]) / (curve["x"][1] - curve["x"][2])
    fk2= (curve["y"][2] - curve["y"][3]) / (curve["x"][2] - curve["x"][3])
    fk3= (curve["y"][3] - curve["y"][4]) / (curve["x"][3] - curve["x"][4])

    if input < curve["x"][1] then
        out = curve["y"][1] + FDY;
    elseif input >= curve["x"][1] and input < curve["x"][2] then    
        out = fk1 * (input - curve["x"][1]) + curve["y"][1] + FDY
    elseif input >= curve["x"][2] and input < curve["x"][3] then
        out = fk2 * (input - curve["x"][2]) + curve["y"][2] + FDY
    elseif input >= curve["x"][3] and input < curve["x"][4] then    
        out = fk3 * (input - curve["x"][3]) + curve["y"][3] + FDY
    else
        out = curve["y"][4] + FDY
    end
 return out
end

curve = {}
curve["x"] = {-20,-10,0,20}
curve["y"] = {80,70,65,18}

--offset=2
--log(linear_by_table(20,curve,offset))
log(linear_by_table(-15,curve))

(16.01.2025, 17:08)Erwin van der Zwart Wrote: For the outdoor temp combined with a curve i usually use a 3 days average, this can simply be done by attaching a trend to your measurement object and use this small script.

Code:

require('trends')
dateslastthreedays = {}
dateslastthreedays['start'] = os.date('*t', os.time() - (86400 * 4))
dateslastthreedays['end'] = os.date('*t', os.time() - (86400 * 1))
threedaysaverage = trends.fetchone('OUTDOOR TEMP', dateslastthreedays)

Quote:require('trends')

-- Define time range for the timespan
local lastninehours = {}
lastninehours['start'] = os.date('*t', os.time() - (3600 * 9)) -- 9 hours back
lastninehours['end'] = os.date('*t', os.time()) -- Current time

-- Fetch the average temperature for the timespan
local ninehoursaverage = trends.fetchone('Utetemp', lastninehours)

-- Fetch the current temperature from KNX address 0/3/0
local currenttemperature = grp.getvalue('0/3/0') -- Assumes grp.getvalue function is used

if ninehoursaverage and currenttemperature then
    -- Calculate the highest value between the average temperature and the current temperature
    local highesttemperature = math.max(ninehoursaverage, currenttemperature)
   
    -- Send the highest value to KNX address 5/5/20
    grp.write('5/5/20', highesttemperature)
   
    -- Log both the average temperature and the temperature sent
    log("Average temperature for the last 9 hours: " .. tostring(ninehoursaverage))
    log("Temperature sent to 5/5/20: " .. tostring(highesttemperature))
else
    log("Could not fetch the average temperature or the current temperature.")
end

(17.01.2025, 08:18)admin Wrote: KB doc needs updating. It's possible to fetch data for the given period if start/end is a not a table but a timestamp number.

Fetch data for the last hour:

Code:

date = os.date('*t') -- current date as a table
time = os.time(date, true) -- convert UTC timestamp

-- fetch data for the last hour (3600 seconds)
datarange = {
  ['start'] = time - 3600,
  ['end'] = time,
}

data = trends.fetch('trend name', datarange)
log(data)

Quote:require('trends')

-- Function to calculate time range based on hours and days
local function get_time_range(start_hours, start_days, end_hours, end_days)
    local date = os.date('*t') -- current date and time as a table
    local current_time = os.time(date, true) -- convert to UTC timestamp
    local start_time = current_time - (3600 * start_hours + 86400 * start_days) -- calculate start time
    local end_time = current_time - (3600 * end_hours + 86400 * end_days) -- calculate end time

    return {
        ['start'] = start_time,
        ['end'] = end_time
    }
end

-- Define time range (replace the number of hours and days with your values)
local start_hours_back = 0 -- hours back from current time for start time
local start_days_back = 1 -- days back from current time for start time
local end_hours_back = 0 -- hours back from current time for end time
local end_days_back = 0 -- days back from current time for end time
local time_range = get_time_range(start_hours_back, start_days_back, end_hours_back, end_days_back)

-- Specify resolution for 5-minute data (360 seconds)
local resolution = 360

-- Fetch average temperature for the time period with specified resolution
local periodaverage = trends.fetchone('Utetemp', time_range, resolution)

-- Fetch the current temperature from KNX address 0/3/0
local currenttemperature = grp.getvalue('0/3/0') -- Assuming grp.getvalue function is used

if periodaverage and currenttemperature then
    -- Calculate the highest value between the average temperature and the current temperature
    local highesttemperature = math.max(periodaverage, currenttemperature)

    -- Send the highest value to KNX address 5/5/20
    grp.write('5/5/20', highesttemperature)

    -- Log both the average temperature and the temperature sent
    log("Average temperature for selected period: " .. tostring(periodaverage))
    log("Temperature sent to 5/5/20: " .. tostring(highesttemperature))
    log("Current temperature at 0/3/0: " .. tostring(currenttemperature))
else
    log("Could not fetch the average temperature or the current temperature.")
end