Lower and upper bounds (for both ingredients and groups) must be between 0 and 1, representing fractions that sum to 1 (i.e. 100%) across the whole formulation. Ex: 0.25 represents 25%. A group's bounds constrain the SUM of all its ingredients and apply only when at least one of its ingredients is present. By default, ingredients are optionally included in any given formulation from the generator: a positive lower bound applies only when thatingredient is included. Mark an ingredient as required to force it into every formulation within its min/max bounds. Each group can also limit how many of its ingredients appear per formulation.