Possible error

Today I have discovered a possible error in the codes I use in my PhD studies. The error is in a subroutine that calculates the velocity gradients of the system. This program is being in use for almost 15 years, and no one has ever spotted this error. If I am mistaken, and I just have missed something, and in the end there is no mistake, excelent! Then life goes on... But, if I am not mistaken, and the error really exists, then the results already published using this program will have to be reviewed.

It is the second error I found in the codes. The first one, fortunately was in a function that was used only once over the program. After the change, the new results did not have any difference from the previous results. This second error was in a function that was called thousands, maybe millions of times, during the course of the program. The results after the changes were totally different from the previous ones.

I have showed it to my advisor, and she also thought that there was an error there. I have also sent an e-mail to my co-advisor in the US, reporting what I have found. She still did not reply... She was one of the people who wrote the program years ago, and use it ever since... I am just waiting her reply to be sure of the mistake, or to know that the mistake was mine... I just hope the mistake was not mine!

Waiting.

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