BookmarkSubscribeRSS Feed
mwechtal

Community Trekker

Joined:

Jan 19, 2012

Is there an inverse to the Day Of Year() function?

I have a day of year column, and need to convert it to a date. I've wracked my brain over this. There's probably a simple solution but it escapes me.

1 ACCEPTED SOLUTION

Accepted Solutions
Jeff_Perkinson

Community Manager

Joined:

Jun 23, 2011

Solution

Re: Is there an inverse to the Day Of Year() function?

I assume you have a year column as well.

If so, you just need to multiply your Day of Year column by the number of seconds in a day (the In Days(1) function will give you this) and add it to the value for December 31 of the previous year. It sounds worse in prose than it really is.

:Day of Year * In Days(1) + Date DMY(31, 12, :Year - 1)

12394_JMPScreenSnapz027.png

12404_JMPScreenSnapz028.png

-Jeff

-Jeff
2 REPLIES
Jeff_Perkinson

Community Manager

Joined:

Jun 23, 2011

Solution

Re: Is there an inverse to the Day Of Year() function?

I assume you have a year column as well.

If so, you just need to multiply your Day of Year column by the number of seconds in a day (the In Days(1) function will give you this) and add it to the value for December 31 of the previous year. It sounds worse in prose than it really is.

:Day of Year * In Days(1) + Date DMY(31, 12, :Year - 1)

12394_JMPScreenSnapz027.png

12404_JMPScreenSnapz028.png

-Jeff

-Jeff
mwechtal

Community Trekker

Joined:

Jan 19, 2012

Re: Is there an inverse to the Day Of Year() function?

Perfect! The data is all this year so far, so I don't need the year column yet.

Thanks! Yes that was simpler than I thought. I was getting frustrated, and I nearly did in in {shudder} Excel, but then I would have had to copy it back and forth every few days.