<div>
i've sorted this out on my own, but i have another maple question, if anyone can help. 
 
i need to create proceedures to check relations for properties of reflexivity and transitivity 
 
reflexitive rule - if Y is a subset of tX then X -&gt; Y 
Transitive Rule - if X -&gt; Y &amp;&nbsp;Y -&gt; Z, then X -&gt; Z 

</div>

i've sorted this out on my own, but i have another maple question, if anyone can help.

i need to create proceedures to check relations for properties of reflexivity and transitivity

reflexitive rule - if Y is a subset of tX then X -> Y
Transitive Rule - if X -> Y & Y -> Z, then X -> Z


<div>
<div class="content wysiwyg-content">
&gt; buildrelation:=proc(s1::set,s2::set,z::relation) 
&gt;&nbsp;local x, y, ans,rel; 
&gt;&nbsp;ans:= NULL; 
&gt;&nbsp; 
&gt;&nbsp;for x in s1 do 
&gt;&nbsp; &nbsp;for y in s2 do 
&gt;&nbsp; &nbsp; if z then 
&gt;&nbsp; &nbsp; &nbsp; ans:=ans,[x,y]; 
&gt;&nbsp; &nbsp; fi; 
&gt;&nbsp; &nbsp;od; 
&gt;&nbsp;od; 
&gt;&nbsp;return({ans}); 
&gt;&nbsp;end: 
&gt;&nbsp;trace(buildrelation); 
 
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; buildrelation 
 
&gt;&nbsp;buildrelation({$1..3},{$1..3},x&lt;y); 
{--&gt; enter buildrelation, args = {1, 2, 3}, {1, 2, 3}, x &lt;&nbsp;y 
 
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;ans := 
 
 
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; x := 1 
 
 
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; y := 1 
 
&lt;-- ERROR in buildrelation (now at top level) = &quot;cannot determine if this expression is true or false: %1&quot;} 
Error, (in buildrelation) cannot determine if this expression is true or false: x-y &lt;&nbsp;0 
 
 
 
the above works if i put x&lt;y directly in the program, but not when i give input it as the relationship &quot;z&quot;. 
 
any idea how i can correct this? 

</div>
</div>

> buildrelation:=proc(s1::set,s2::set,z::relation)
> local x, y, ans,rel;
> ans:= NULL;
> 
> for x in s1 do
> for y in s2 do
> if z then
> ans:=ans,[x,y];
> fi;
> od;
> od;
> return({ans});
> end:
> trace(buildrelation);

 buildrelation

> buildrelation({$1..3},{$1..3},x<y);
{--> enter buildrelation, args = {1, 2, 3}, {1, 2, 3}, x < y

 ans :=


 x := 1


 y := 1

<-- ERROR in buildrelation (now at top level) = "cannot determine if this expression is true or false: %1"}
Error, (in buildrelation) cannot determine if this expression is true or false: x-y < 0



the above works if i put x<y directly in the program, but not when i give input it as the relationship "z".

any idea how i can correct this?

maple 8 relation problem

A miscellany is defined as a "collection of various pieces of writing by different authors", but it has come to mean something "Of items gathered or considered together of various types or from different sources" or "a collection or group composed of members or elements of different kinds". The word "miscellaneous" comes from the Latin word "miscere", meaning "to mix." You might have heard the expression "a mixed bag," which applies when you don't quite know what you're going to get. More commonly, a miscellaneous group is made up of an odd group of things that don't fit anywhere else.