2d Minimum block return wrong idx and value

Hi, I'm looking for the min value in a 160000*1 vector using 2d minimum block from computer vision toolbox. There are some nan element in this vector. However, I always receive NaN as a result even though there exists a min value.

I compare this result with Min block, and It does give me something.

This is my model setup, inport 1 receive a vector(16000*1) and the 2-d minimum find the min value and return the idx and value.

This is the result(scope on the right bottom). The ch1 receive the result from 2-d Minimum block and ch2 receive the result from min block.

I'm wondering if this is a bug or I did something stupid?

Thanks,

Alex