Is there a math function that increases when >0 and constant when <0 WITHOUT using piecewise functions.
Is there a mathematical function that is constant at 0, but once it hits 0, it begins increasing. I dont care what kind of increasing function it is: e, parabola, etc. 
I am trying to avoid piecewise function. 
Is there a math function that increases when >0 and constant when <0 WITHOUT using piecewise functions.
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Is there a mathematical function that is constant at 0, but once it hits 0, it begins increasing. I dont care what kind of increasing function it is: e, parabola, etc. 
I am trying to avoid piecewise function. 