when viewing output from an UCI compatible engine in Arena, the output shows the ply with either a '+', '-', or nothing behind it, such as
When monitoring the output from the engine, the +/-/blanks codes map to:
+ = upperbound
- = lowerbound
blank = ?
in code, when writing to UCI, does the upperbound mean a beta cutoff occurred, or does it mean that alpha is the "upper bound" since the score failed lower than alpha?
and what does blank mean? i thought that that might refer to the exact score, but sometimes there are two blank entries in a row, such as:
what is the practice here? some possible outputs are anytime alpha is raised, anytime there is a beta cutoff, whenever there is an exact score found.