Figure 15: Dialog to create the EStat input script. position r = 10 . 0 cm corresponds to x = y = 7 . 071068 cm. Click the Point calculation tool. We can specify the location by moving the mouse inside the solution volume and clicking the left button. This selection method is not accurate enough for the comparison. Instead, press the F1 key after starting the Point calculation tool to enter coordinates manually. Fill in the x - y values and click OK . Values of several calculated quantities are displayed at the bottom. The calculated values of potential (36.90767 V) and electric field (910.23111 V/m) agree with the theoretical value to within thousands of a percent.
Rather than copy numbers from the screen, why not let EStat write them for us? Click the Open data record command and accept the default name CoaxialCylinders.DAT . Now, every time we do an interactive calculation, the results are recorded in the text file. For example, choose the menu command Analysis/Volume integrals . The results are displayed on the screen and written in the file CoaxialCylinders.DAT . You can inspect the file with an external editor. To use the internal EStat editor, click the Close data record command first because two instances of a same file cannot be opened simultanously in a program.
Open the data file to see the result of the calculation, the volume integrals of the field-energy-density: Quantity: Energy Global integral: 1.708936E-07 RegNo Integral ========================== 1 1.708936E-07 2 9.881184E-37 22