Variable use between CAS and Home.

[Rudi]

Variable use between CAS and Home.
I have written a new user defined function. It change lowercase x, y, z variables to uppercase X, Y, Z variables.
I have defined the Name of the function in the follow:
CHANGE xyz to XYZ
CH xyz 2 XYZ

Code:
#cas
// To use Variables between CAS and Home
// Writen by Rudi Steeger
// Input an Formular with Lowercase x, y, z Variables
// Output Uppercase X, Y, Z Variables
// Important Use the Program only in CAS View!
CHxyz2XYZ(cmd):=
BEGIN
RETURN subst(cmd,([x,y,z]) = (trn([['X'],['Y'],['Z']])));
END;
#end


// Examples (Only in CAS View):
// CHxyz2XYZ(2*x*y^2*z+5*x^2-5*y+3*z)
// ==> 2*X*Y^2*Z+5*X^2-5*Y+3*Z

// f:=2*x*y^2*z+5*x^2-5*y+3*z
// ==> 2*x*y^2*z+5*x^2-5*y+3*z

// CHxyz2XYZ(f)
// ==> 2*X*Y^2*Z+5*X^2-5*Y+3*Z

// CHxyz2XYZ(2*x+5*x^2-5)
// ==> 5*X^2+2*X-5

// F1:=CHxyz2XYZ(2*x+5*x^2-5)
// ==> (X)->2*X+5*X^2-5