Millisecond Forums

Hello, I am working on changing around the syntax posted below. The current setting is for 24 trials with a 7:7:10 ratio (targetAleft, attributeA and attributeB, respectively). Instead, I would like to have 18 trials where any of the targetAleft, attributeA, and attributeB may be randomly selected without replacement. Any ideas on how to change the syntax below to do this?

Thanks in advance! 

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Note: presents the trials in a 7:7:10 ratio => 14 (good + target) on responsekey_left and 10 (bad) on responsekey_right
<block practice_compatibletest>
/ bgstim = (attributeAleft, orleft, targetAleftmixed, attributeBright)
/ trials = [1=instructions;
2-25 = noreplace(targetAleft, targetAleft, targetAleft, targetAleft, targetAleft, targetAleft, targetAleft,
attributeA, attributeA, attributeA, attributeA, attributeA, attributeA, attributeA,
attributeB, attributeB, attributeB, attributeB, attributeB, attributeB, attributeB, attributeB, attributeB, attributeB)]
/ responsemode = correct
</block>