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<DIV><FONT face=Arial size=2>Hello,</FONT></DIV>
<DIV><FONT face=Arial size=2>Having just joined this list, I should appreciate
assistance with the following two questions.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Question 1:<BR>Given a node name, how can I
subsequently determine the coordinates x and y?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>As the simplest example, if I have previously
defined node A as a point node<BR>\pnode(10,20){A}<BR>how can a macro (command)
that uses node A, recover the original coordinates x and y?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>There are various applications for which this would
be useful.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Question 2:<BR>For example, to measure the distance
between two nodes. Let this be the related question 2: how to measure
horizontal and vertical distances between two nodes.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>It is related to question 1 since if it is possible
to measure the horizontal and vertical distances between two nodes, one of which
is the origin, it provides a solution to question 1.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I have tried various indirect ways to measure the
distance between nodes. For
example,<BR>\pnode(10,20){A}<BR>\pnode(30,40){B}<BR>\newlength{\temp}<BR>\SpecialCoor<BR>\settoheight{\temp}{%<BR>\psframe(A)(B)<BR>}%<BR>\NormalCoor</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>The idea was to define an object based on the two
nodes and then measure the height of the object, thereby determining the
vertical distance between the two nodes. Similarly, \settowidth could in
principle be used to measure the horizontal distance. However, this
approach is unsuccessful as a result of the PSTricks object (\psframe in this
example) having no physical size! This is as documented on page 41 of the
original manual.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>On the same page of the manual it states that a
pspicture can be used to reserve a certain size. So, for attempt two, I
tried:</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial
size=2>\pnode(10,20){A}<BR>\pnode(30,40){B}<BR>\newlength{\temp}<BR>\SpecialCoor<BR>\settoheight{\temp}{%<BR>\begin{pspicture}(A)(B)%<BR>\end{pspicture}<BR>}%<BR>\NormalCoor</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>TeX seems to be unhappy with the use of Special
Coordinates for pspicture! The error message is<BR>! Argument of
\pst@@picture has an extra }</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I tried using other types of Special Coordinates
unrelated to nodes<BR>\begin{pspicture}(! 10 20 )(! 30
40)%<BR>\end{pspicture}<BR>Again TeX is unhappy (same error message). The
conclusion is that pspicture only works with Cartesian coordinates.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Any ideas on solutions to these two questions would
be much appreciated!</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Douglas</FONT></DIV></BODY></HTML>