7 Replies Latest reply on May 17, 2012 2:42 PM by Jerry Brian

    Parametric equations

    Mike Mongan

      How do I enter a parametric equation in x, y, z into the equation editor.  Is there a particular format that works?  How about for r, theta, phi or r, theta , z?

        • Re: Parametric equations
          Jerry Steiger

          Mike,

           

          I don't use equations, so I'm not going to be of much help, but perhaps my answer will prompt someone more knowledgeable to kick in.

           

          What do you mean when you say parametric? I have seen people set up equations like x=f(t), y=g(t), z=h(t). Is that what you are referring to?

           

          I don't believe SolidWorks knows about spherical or cylindrical coordinates, only Cartesion.

           

          Jerry Steiger

          • Re: Parametric equations
            Jason Kerns

            Is this what you are looking for?

            Operator

            Name

            Notes

            +

            plus sign

            addition

            -

            minus sign

            subtraction

            *

            asterisk

            multiplication

            /

            forward slash

            division

            ^

            caret

            exponentiation

             

             

             

            Function

             

             

            sin (a)

            sine

            a is the angle; returns the sine ratio

            cos (a)

            cosine

            a is the angle; returns the cosine ratio

            tan (a)

            tangent

            a is the angle; returns the tangent ratio

            sec (a)

            secant

            a is the angle; returns the secant ratio

            cosec (a)

            cosecant

            a is the angle; returns the cosecant ratio

            cotan (a)

            cotangent

            a is the angle; returns the cotangent ratio

            arcsin (a)

            inverse sine

            a is the sine ratio; returns the angle

            arccos (a)

            inverse cosine

            a is the cosine ratio; returns the angle

            atn (a)

            inverse tangent

            a is the tangent ratio; returns the angle

            arcsec (a)

            inverse secant

            a is the secant ratio; returns the angle

            arccosec (a)

            inverse cosecant

            a is the cosecant ratio; returns the angle

            arccotan (a)

            inverse cotangent

            a is the cotangent ratio; returns the angle

            abs (a)

            absolute value

            returns the absolute value of a

            exp (n)

            exponential

            returns e raised to the power of n

            log (a)

            logarithmic

            returns the natural log of a to the base e

            sqr (a)

            square root

            returns the square root of a

            int (a)

            integer

            returns a as an integer

            sgn (a)

            sign

            returns the sign of a as -1 or 1

            For example: sgn(-21) returns -1

             

             

             

            Constant

             

             

            pi

            pi

            ratio of the circumference to the diameter of a circle (3.14...)

            • Re: Parametric equations
              Mike Mongan

              Hi Jerry and Jason,

              Yes that is how a parametric equation is stated.  And yes those are the standard functions. My old CAD system, Vectorworks which I still have, allows me to create a 3d surface using parametric equations.  I have to write a script to do it but it works pretty good.  I used it to create a turbine blade by formula.  In the script I  can enter commands to "place a point" etc with fields for x, y, z which is where the formula goes. Their commands are openly available.  I see no such functionality in Solidworks which I though was a superior system when I bought it.  So now I have to create my blades in Vectorworks and export the surface into Solidworks. It is a compund curve so I can't just draw it on a plane and project it.