[R-sig-eco] Using the ANN in lake system

[javad bayat]

 Dear all;
 I am using the ANN to predict the concentration of DO in
 a lake system but I do not know why all the predicted values are
 similar? Here are my codes:
 
 library(neuralnet)
 library(nnet)
 ## fit a simple model
 fit  <- neuralnet(DO ~ Day,data = ss1)
 ## create new data into the future
 futuredata <- expand.grid(Day = 589:1000)
 ## do predictions
 predictions <- compute(fit, futuredata)
 
 Here is my data: ss1: 
station     Day     DO 
kanal         1            8.3
kanal         8          8.6
kanal         14    8.4
kanal         17    7.9
kanal         28    7.1
kanal         35    6.7
kanal         47    6.5902
kanal         54    6.8475
kanal         63    6.5487
kanal         70    6.2416
......       ....          .....
......       ....          .....
......       ....          .....
......       ....          .....
kanal      475    6.8
kanal            496    7.63
kanal            510    7.39
kanal            536    7.72
kanal            567    8.53
kanal             588    9.14



Many thanks.
Regards.