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Variable Grouping Keyword

<VariableGrouping N>
<vg N>

    Scramble parameter that enables variable group sizes. For information on traditional scrambling see Scrambling. N specifies a divisor, items that are consecutive and that have identical item numbers when divided by N are considered to be in the same group.

    When determining the block size, the value for the S parameter, as with the traditional grouping parameter, is in numbers of groups.
   
    It is important to note that variable grouping completely ignores fixed blocks (the contents of the item file between $ symbols), any item numbers occurring there are ignored for the purposes of determining whether the two items surrounding the fixed block are part of the same variable group. Which brings up a difference between the way the traditional G parameter and <vg> work, and that is their treatment of a fixed block when it occurs in the middle of a group -- which is a rather tenuous thing to do in the first place. Traditional grouping will move that fixed block to the end of the group, variable grouping will move it to the start of the group.

    For example:

s1 <vg 100>

$0 "variable grouping" , <ln 2> "Hit SpaceBar to Continue";$

101 "101";
102 "102";
103 "103";
104 "104";
105 "105";
$0 "within group";$
106 "106";
107 "107";
108 "108";
109 "109";

201 "201";
202 "202";
203 "203";

$0 "inter group";$

301 "301";
302 "302";
303 "303";
304 "304";
305 "305";
306 "306";

$0 "end"l;$

    Can produce the following when scrambled:

s1 <vg 100>

0 "variable grouping" , <ln 2> "Hit SpaceBar to Continue";

0 "within group";

301 "301";
302 "302";
303 "303";
304 "304";
305 "305";
306 "306";

201 "201";
202 "202";
203 "203";

0 "inter group";

101 "101";
102 "102";
103 "103";
104 "104";
105 "105";
106 "106";
107 "107";
108 "108";
109 "109";

0 "end"l;




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