Ernesto, and the group,
Again, Ernesto's many examples of trees are helpful in my quest to create
tableau proofs in LyX. But these examples still don't have the exact
structure I need.
I've attached (to earlier messages) a pdf file containing an example of
what I'm seeking, but apparently there is trouble viewing it. I don't
understand this, since in trial e-mails I've sent to myself the file can be
opened and read using Adobe Reader. I'm using gmail and attaching the file
in the usual way. I'll attach it again to this message and hope for better
results.
Here's a crude attempt to represent what I'm after. (I hope it comes
through ungarbled.)
not((P or (P & Q)) -->P)
P or (P & Q)
not P
/ \
/ \
/ \
P P & Q
x P
Q
x
Each of the seven nodes is a formula of a specified formal language. (In
this case it's simple propositional logic.) Notice that there are no lines
(vertical or sloping) between any of the nodes except when branching
occurs. The only lines in the tree are the sloping ones that indicate
branching. It is this feature that I'm unable to create. (I know LyX
pretty well, but I know practically nothing about LaTeX.)
If I could create trees in which nodes are connected with straight lines
only when branching occurs, I'd be well on my way.
Bill
