MaplePrimes - answers and comments on Question, Problem with Graph

Vertices need to be integers, symbols, or strings

Carl Love — Thu, 21 Mar 2013 02:05:24 Z

GraphTheory:-Graph vertices need to be integers, symbols, or strings; arbitrary expressions are not allowed. So 2, `*`, function, cos, y, and z are valid; but 2*y, 3*z, and cos(x+2*y) are not.

Ok

JamesK — Thu, 21 Mar 2013 02:09:18 Z

I see....What do you recommend I should do?

I replaced Tree := Tree, {whattype(elem),elem}

JamesK — Thu, 21 Mar 2013 02:37:56 Z

I replaced Tree := Tree, {whattype(elem),elem} with Tree := Tree, {whattype(elem)} and I get the following output and error :

Error, (in GraphTheory:-Graph) invalid edge/arc: {2}

Edges need two vertices

Carl Love — Thu, 21 Mar 2013 03:09:58 Z

@JamesK

I replaced Tree := Tree, {whattype(elem),elem} with Tree := Tree, {whattype(elem)} and I get the following output and error :

Error, (in GraphTheory:-Graph) invalid edge/arc: {2}

Well, of course. Every edge needs two vertices.

@Carl Love I know:P.....I've also tried Tree

JamesK — Thu, 21 Mar 2013 03:24:16 Z

@Carl Love I know:P.....I've also tried Tree := Tree, {whattype(expr)},{whattype(elem)}; but I get the same error...what can I do?

convert to string or symbol

Carl Love — Thu, 21 Mar 2013 03:26:12 Z

@JamesK I see....What do you recommend I should do?

To answer that simplistically: Anything can be converted to a string with convert(..., string) or sprintf("%a", ...); anything can be converted to a symbol with convert(..., symbol) or nprintf("%a", ...).

But since I know where you're going with this, I suggest that you study closely my FunctionToTree module in the other recent thread here. You're going to encounter exactly the same problems that I did when writing that, even though you're not first applying ToInert.