Creating time series frequency interval =1min and forecasting

rstudio

#1

Hi I am forecasting data based on interpolated data. My interpolated data: metervalue of dataID=1103data as below:

dataid,meter_value
1103,183138
1103,183138
1103,183138
1103,183138
:
:
1103,197015.9857
1103,197015.9928
1103,197016

output of time(zz) as below.

x,dataid,meter_value
27/10/2015 19:50
27/10/2015 19:51
27/10/2015 19:52
27/10/2015 19:53
:
:
24/2/2016 0:38
24/2/2016 0:39
24/2/2016 0:40

Based on that interpolated data,I am trying to forecast 6 months data starting from 24/02/2016 0:41 to 24/07/2016 0:41.

I tried to create myts with 1min frequency interval for predicting data using ETS and HoltWinter but, all forecasting plot are weird for 1 min interval data. I could not get 80% and 95% high low data range with predicted data.

My interploated data as below:

to.minute <- function(x) as.POSIXct(trunc(as.POSIXct(x, origin = "1970-01-01"), "mins"))
z <- read.csv.zoo("test_1103.csv", FUN = to.minute, aggregate = function(x) tail(x, 1))
zz <- na.approx(as.zoo(as.ts(z)))
time(zz) <- as.POSIXct(time(zz), origin = "1970-01-01")

My forecasting data as below:

myts <- ts(zz$meter_value, start = c(2015,10,27,19,50), end = c(2016,02,24,0,40), frequency = 10080)

forecast(myts,12)
           Point Forecast    Lo 80    Hi 80    Lo 95    Hi 95
2016.00020       183248.6 183248.6 183248.6 183248.6 183248.6
2016.00030       183248.6 183248.6 183248.6 183248.6 183248.6
2016.00040       183248.6 183248.6 183248.6 183248.6 183248.6
2016.00050       183248.6 183248.6 183248.6 183248.6 183248.7
2016.00060       183248.6 183248.6 183248.7 183248.6 183248.7
2016.00069       183248.6 183248.6 183248.7 183248.6 183248.7
2016.00079       183248.6 183248.6 183248.7 183248.6 183248.7
2016.00089       183248.7 183248.6 183248.7 183248.6 183248.7
2016.00099       183248.7 183248.6 183248.7 183248.6 183248.7
2016.00109       183248.7 183248.6 183248.7 183248.6 183248.8
2016.00119       183248.7 183248.6 183248.7 183248.6 183248.8
2016.00129       183248.7 183248.6 183248.8 183248.6 183248.8

How could i change the format of point forecast to "yyyy-mm-dd hh:mm" what is the meaning of "four decimal values" (eg.2016.00129) in point forecast ?

Same for HoltWinter Forecast method: I could not get the plot with 80% and 95% range interval ad prediction data.

HoltWinters(x = myts, beta = TRUE, gamma = FALSE)

Smoothing parameters:
 alpha: 0.9999424
 beta : TRUE
 gamma: FALSE

Coefficients:
          [,1]
a 1.832486e+05
b 6.906077e-03

forecast(hw, 12)
           Point Forecast    Lo 80    Hi 80    Lo 95    Hi 95
2016.00020       183248.6 183248.6 183248.6 183248.6 183248.6
2016.00030       183248.6 183248.6 183248.6 183248.6 183248.6
2016.00040       183248.6 183248.6 183248.6 183248.6 183248.6
2016.00050       183248.6 183248.6 183248.6 183248.6 183248.7
2016.00060       183248.6 183248.6 183248.7 183248.6 183248.7
2016.00069       183248.6 183248.6 183248.7 183248.6 183248.7
2016.00079       183248.6 183248.6 183248.7 183248.6 183248.7
2016.00089       183248.7 183248.6 183248.7 183248.6 183248.7
2016.00099       183248.7 183248.6 183248.7 183248.6 183248.7
2016.00109       183248.7 183248.6 183248.7 183248.6 183248.8
2016.00119       183248.7 183248.6 183248.7 183248.6 183248.8
2016.00129       183248.7 183248.6 183248.8 183248.6 183248.8
Both ETS and HoltWinter Expected forecasted dataplot

Is "myts" with 1 min frequency interval correct? How should i change the plot so that I can see the 80% and 95% range with prediction data.