3 columns (Year, Day, Time) How do I make them Mon/Day/Year on a graph?

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I have 3 columns on my chart from my data files

They come in as Year, Day (numerically 254 or 365 for example), and Time (either 0000 or 1200)

How can I get these 3 columns to graph as one date?
Here is a solution which I have not tested:

Function CreateDateTimeWave(year, dayOfYear, timeOfDay, newWaveName)
    Wave year
    Wave dayOfYear
    Wave timeOfDay          // 1200 represents noon
    String newWaveName      // Name for new wave
    
    Variable numPoints = numpnts(year)      // Assume all input waves have the same number of points
    
    Make/O/N=(numPoints)/D $newWaveName
 
    Wave w = $newWaveName               // Create wave reference to new wave
    SetScale d, 0, 0, "dat", w              // Tell Igor it is a date/time wave
    
    w = date2secs(year, 0, 0)               // Convert to Igor date/time format (seconds since 1/1/1904)
    
    w += dayOfYear * 60*60*24           // Add seconds corresponding to day of year
    
    w += (timeOfDay / 100) * 60*60      // Add seconds corresponding to time of day
End


You can use the resulting wave as the X wave of an XY pair for graphing.

August 16, 2008 at 06:21 am - Permalink