When I used "gamfit(data)", it says "X must be non-negative."

I have 45000*1 data table and all of values are non negative.

When I used "gamfit(data)", it says "X must be non-negative." Would you help me please?

[Walter Roberson]

What shows up for

nnz(data<0)

[Chris]

It says "1"

Answer 1

[Walter Roberson]

[r, c, s] = find(data<0);

compose("Row %d column %d contains %g", r, c, s)