created Expr for constraints, for switch to Exprs
created Expr for constraints, for switch to Exprs

JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software