negative eignevalue issue

[mapi]

Hi,
The msg files say that the matrix has negative eigenvalues. But it also continues to solve the problem. And it finally gives right result.

So my questions are:
1)what heppens? Is the matrix not constructed correctly?

2) Even, the matrix has negative eigenvalues, is the result that abaqus obtains right?

Thanks.

 

[Yoman228]

It is perfectly fine if the message show up in an increment where it did not convert.

If it is a converted step, you need to look into the model carefully, as those steps could have a more then one solution.

You can eliminate those messages by putting more constraint or put some imperfection in the model. But if the results look correct. You do not need to worry them.