I'm trying to define a new command for scalar product. So far, it looks like this:
However, when I was trying to put something riddiculously high in one of the fields, the separator (|) remained the same height. I tried modifying the command:
However, that doesn't work; by putting a matrix in one of the fields I get an error. Putting anything else produces an error as well. Why? I tried substituting | for other vertical lines, but it didn't help.