using Calculus expression="X*Y^2/(X+Y)" trans="f(t)="*replace(replace(expression, "X"=>"t[1]"),"Y"=>"t[2]") eval(Meta.parse(trans)) X=0.001 Y=0.001 println("Gradient de f au point (",X,",",Y, ") évalué numériquement") println(Calculus.gradient(f,[X,Y])) (g,h)=differentiate(expression,[:X,:Y]) println("Gradient de f au point (",X,",",Y, ") évalué symboliquement") println([eval(g),eval(h)])