Sheeking a fonction ( select half group )

[cramboel]

Hello i'm trying to make maccro to help me create my shape and effect And i would know how to : select "half" off a group , not like this :
<step pause="0.001">Command.RunCommand("PATTERN 8 IN 16")</step>
But somehow like this
<step pause="0.001">Command.RunCommand("HALF")</step>
And quarter too ...
i'm fine with the 1 in 4 but not with more

ty