opposite EOF loading
Added by S BR over 6 years ago
Hi All,
I am doing the EOF calculation for 5 different models. I get the correct spatial pattern (Ex: PDO) for 4 different models. However, I get reverse spatial pattern in one of the models. However, I get the correct spatial pattern in this model if I multiply the values with -1. I don't know why such problem occurred in this model.
Now, I am calculating the EOF coefficient for the respective EOFs. Do I need to multiply again the values (time series) with -1 for the model I get the reverse EOF pattern.
Does anyone have experienced such issues.
SB
Replies (2)
RE: opposite EOF loading - Added by Adrian Tompkins over 6 years ago
The sign of the EOF is arbitrary, so you always need to check and reverse sign when necessary.
RE: opposite EOF loading - Added by S BR over 6 years ago
Hi,
Thanks for your reply. Now I understand about reversing the sign when necessary.
I would like to know if I also need to reverse the sign of the EOF coefficient (time series) or it is independent of EOF sign.
My query is, do I need to reverse the sign of the EOF coefficient if I reverse the sign of the EOF pattern.
I calculate the EOF coefficient as given below.
cdo eof,3 anom_file eval_file eof_file
cdo eofcoeff eof_file anom_file obase
Thanks
SB