what does \z mean?

Question

In some codes I encountered some \z command, for example:

\pgfmathrandomitem\z{mylist}\z\prunelist{mylist}

from this question: Generating random numbers without repetitions. What exactly does it mean?

just a macro? but if you look at the accepted answer of the linked question, there is no definition of \z... and the code, cut-and-pasted on my editor, works — user126154, Jan 30 '15 at 18:33
\pgfmathrandomitem internally makes the necessary definition. — Gonzalo Medina, Jan 30 '15 at 18:34
The answer is not accepted, as there's no check by it, @user126154. I'd strongly suggest you mark it as such — hd1, Jan 30 '15 at 22:08
@hd1 The user was referring to 'the accepted answer of the linked question', and the linked question not only has an accepted answer. It isn't the OP's question in any case, so they couldn't accept an answer if they wanted to. — cfr, Jan 31 '15 at 02:23
@user126154 \z is a control sequence which is very often preferred by @DavidCarlisle . — wipet, Jan 31 '15 at 07:03

score 9 · Accepted Answer · edited Jan 30 '15 at 19:37

9

It's nothing more than a standard macro. Instead of \z you could have used \xxxyyy or any other valid macro name.

The line

\pgfmathrandomitem\z{mylist}

simply selects an item from the mylist list and stores it in the macro \z.

Then

\z\prunelist{mylist}

shows the item stored in \z and removes it from the list.

edited Jan 30 '15 at 19:37

azetina

answered Jan 30 '15 at 18:30

Gonzalo Medina

so the \z\prunelist{mylist} just prune the listo fo the "macro" \z? – user126154 Jan 30 '15 at 18:34
@user126154 \z\prunelist{mylist} removes the item stored in \z from the list. – Gonzalo Medina Jan 30 '15 at 18:38
Ok, now I cut-and-pasted the code, but then I try to use the macro \z elsewhere just by adding \z to some test place and the result is not what I expected – user126154 Jan 30 '15 at 18:47
if I type for instance \pgfmathrandomitem\z{mylist}\z\prunelist{mylist}\z then the result of the last \z is the successor, in the list order, of the firs \z – user126154 Jan 30 '15 at 18:48
i would like indeed store a random element of mylist in a macro that can be used elsewhere – user126154 Jan 30 '15 at 18:51
@user126154 That's exactly what \pgfmathrandomitem does: `\documentclass{article} \usepackage{tikz}
\begin{document}

\pgfmathdeclarerandomlist{mylist}{{one}{two}{three}{four}{five}{six}{seven}} \pgfmathrandomitem\z{mylist}

\z\z\z

\end{document}`
– Gonzalo Medina Jan 30 '15 at 18:52
@user126154 Perhaps you are trying something like this? `\pgfmathrandomitem\z{mylist} \edef\xxxx{\z}
\xxxx \xxxx`
– Gonzalo Medina Jan 30 '15 at 18:56
I'm trying the code in the linked question and then, using this line \pgfmathrandomitem\z{mylist}\z\prunelist{mylist}\z the results of the first and last occurence of the \z are different! – user126154 Jan 30 '15 at 19:22
Let us continue this discussion in chat. – user126154 Jan 30 '15 at 19:25

1 Answers1