[R] using its to import time series data with uneven dates

[Sheri Conner Gausepohl]

Good day:

I am trying to use 
readcsvIts("nwr_data_qc.txt",informat=its.format("%Y%m%d%h%M 
%Y"),header=TRUE,sep="",skip=0,row.names=NULL,as.is=TRUE,dec=".")

to read in a file (nwr_data_qc.txt)  that looks like this:

Time         Y      M   D  H   Min    CO2
2000.18790   2000.  3.  9. 18. 30.    373.60
2000.20156   2000.  3. 14. 18. 30.    373.34
2000.22609   2000.  3. 23. 18.  0.    373.01

and  R returns this:

         Y  M  D  H Min    CO2
<NA> 2000  3  9 18  30 373.60
<NA> 2000  3 14 18  30 373.34
<NA> 2000  3 23 18   0 373.01

I have tried every format option on the help page.  How can I read in 
my decimal dates (e.g., 2000.18790)?

Note that these data (CO2) are irregularly spaced in time (Time).

Ultimately I would like to fit a trigonometric polynomial (first 
harmonic) to these data in order to smooth them and obtain values 
between measurements.  Any suggestions you can provide on how to do 
this would be much appreciated.

Thank you for your help.

Sheri

Sheri L. Conner Gausepohl
Graduate Research Assistant
Department of Atmospheric Science
Colorado State University