16 Replies Latest reply: Apr 9, 2012 12:31 PM by ptc-4532331 RSS

    Explicit calculations

    ptc-4532331 Copper

      Good afternoon All,

       

      I understand the basics of explicit functions in MathCAD, however I am not able to figure out how to have an equation list the numerical values of each variable included in an equation. For instance, I am trying to calculate the total surface area of a concrete storm sewer junction box to determine the total formwork needed. The total surface area would be calculated as the sum of the exterior/interior 4 sides and exterior/interior top and bottom. The following is an example of my workflow:

       

      a=sides=2 ft^2

      b=top=3 ft^2

      d=bottom=4 ft^2

       

      f=total=a+b+d

       

      I would like the valuves of a,b and d listed in my equation. When I attempt the explicit calculation I type: f=a+b+d, explicit,a,b,d. The result I receive is: f=a+b+c,explicit,a,b,d-->a,b,d=9 ft^2. How can I have the explicit function show: f=a+b+c=2 ft^2+3 ft^2+4 ft^2=9 ft^2?

       

       

      The tutorial sheets in MathCAD do not show how to have an equation show the values, only the operation shown (i.e. F1=1, A1=2, F1/A1, explicit, F1, A1 --> 1/2=0.5)

       

      Does anyone have an answer or suggestion?

       

      Thank you and I apologize for any confusion.

        • Re: Explicit calculations
          AlanStevens Platinum

          This is what I get in M15:

           

          Explicit.png

          What version of Mathcad are you using?

           

          Alan

           

          NB Also, by right-clicking on the symbolic evaluation you can choose to show the evaluation with = signs rather than arrows.

            • Re: Explicit calculations
              mzeftel Gold

              I get the same results as Alan in Mathcad Prime 2.0.

               

               

              explicit.png

               

              Mona

                • Re: Explicit calculations
                  ptc-4532331 Copper

                  I replied to Alan but I wanted to respond to you, too and hopefully Alan will see this.

                   

                  Below is the actual formulas and variables I used. In lieu of "a" I used SA (for surface area) with the subscript to differentiate between sides, top and bottom. I'm using different numbers for simplification of my question.

                   

                  SA.top := 8ft*4ft

                  SA.top = 32ft^2

                   

                  SA.bottom := 8ft*4ft
                  SA.bottom = 32ft^2

                   

                  SA.sides :=10ft*8ft

                  SA.sides = 80ft^2

                   

                  SA.total := SA.top + SA.bottom + SA.sides

                   

                  The next line shows the result that I receive when trying to apply the explicit function:

                   

                  SA.total, explicit, SA.top, SA.bottom, SA.sides ------> SA.top, SA.bottom, SA.sides

                   

                  I do get numerical values for the example I provided in my original post but I do not get any numerical values in my worksheet for the workflow above, even if I applied the explicit function to the SA.total equation I show above, right below the variables. 

                   

                  Do you have any suggestions?

                    • Re: Explicit calculations
                      AlanStevens Platinum

                      Scott Horowitz wrote:

                       

                      Below is the actual formulas and variables I used. In lieu of "a" I used SA (for surface area) with the subscript to differentiate between sides, top and bottom. I'm using different numbers for simplification of my question.

                       

                      SA.top := 8ft*4ft

                      SA.top = 32ft^2

                       

                      SA.bottom := 8ft*4ft
                      SA.bottom = 32ft^2

                       

                      SA.sides :=10ft*8ft

                      SA.sides = 80ft^2

                       

                      SA.total := SA.top + SA.bottom + SA.sides

                       

                      The next line shows the result that I receive when trying to apply the explicit function:

                       

                      SA.total, explicit, SA.top, SA.bottom, SA.sides ------> SA.top, SA.bottom, SA.sides

                       

                      I do get numerical values for the example I provided in my original post but I do not get any numerical values in my worksheet for the workflow above, even if I applied the explicit function to the SA.total equation I show above, right below the variables. 

                       

                      Do you have any suggestions?

                      Explicit needs to be used where you calculate SA.total:

                      Explicit2.png

                      Alan

                        • Re: Explicit calculations
                          ptc-4532331 Copper

                          I tried that also but see that where the variables are inserted, the operations are printed for each variable, and not the numerical value for each variable. Instead of 32 ft^2 for SA.top the explicit function shows 8ft*4ft.

                            • Re: Explicit calculations
                              AlanStevens Platinum

                              Scott Horowitz wrote:

                               

                              I tried that also but see that where the variables are inserted, the operations are printed for each variable, and not the numerical value for each variable. Instead of 32 ft^2 for SA.top the explicit function shows 8ft*4ft.

                              I see what you mean. You might be stuck with this!

                      • Re: Explicit calculations
                        ptc-4532331 Copper

                        I am using MathCAD 14. I right-clicked to show only equation side and I also tried to hide the left side of the equation but there is a large space. I can attach my worksheet to see if that might help. It will show the actual formula and variables I'm using.