All the calculator programs have a common graphic user interface. This simple interface consists of only 3 user pages:

• INPUT
• RETRY
• SUCCESS

The input data is first entered in the INPUT page and validated. If validation is successful, calculations follow and the results are displayed on the SUCCESS page. If validation fails, the RETRY page is displayed giving the user an opportunity to make corrections and repeat the run.

Any portion of the SUCCESS page (and indeed any page) can be "copied and pasted" on to any Windows compatible application like Word, Excel etc.

The Home button leads to the Menu of available calculations, and the Contact button is self-explanatory.

INPUT PAGE

1. Data: INPUT DATA  This is where the user enters a title (optional), data values & selects options. Clicking on any an input field, will display a prompt in the status bar showing expected range of values for that input variable. In some more complex calculators, an EXAMPLE Of Input/Output link is provided to demo data entry expectations and results; you may edit & use this as starting point.
2. Action:   The Calculate button initiates validation and the computational processes. The Reset button clears all entered data values.
3. Output: OUTPUT VARIABLES & GRAPHS   This gives the user an idea of the kind of variables that will be expected to have values at the end of the calculation process.
4. Theory: THEORY & FORMULAE  This describes the underlying theory, algorithms and equations used in the calculation and the relevant references.

RETRY PAGE

1. Data: INPUT DATA  This is where the user corrects the errors highlighted by the validation process, and has the chance to re-enter a title, data values and/or & select options. Explicit errors messages in red include out-of-range values or logical relations between data items.
2. Action:   Calculate initiates the validation and computational processes. The Reset button clears all the input data values, and returns to the Input Page.
3. Output:  OUTPUT VARIABLES & GRAPHS  This gives the user an idea of the kind of variables that will be expected to have values at the end of the calculation process.

SUCCESS PAGE

1. Data: INPUT DATA   This re-echoes all the values entered by the user which has now resulted in a successful solution. The user may also modify/re-enter data here to begin another cycle of calculation.
2. Action:   If data has been modified in this page, Calculate re-initiates the validation and computational processes. The Reset button clears all the input data values, and returns to the Input Page.
3. Output: RESULTS & GRAPHS   This gives the solution to the problem. If applicable, there may also be an accompanying graph or graphs. All the graphs are interactive to some degree. Moving your cursor over/or clicking on objects in a graph, will lead to a display of the objects value(s). Also, the objects in 3D graphs can be rotated by holding down and dragging the cursor in any desired direction.

PRINTING

1. Printing Update !!! :   Large Graphic images which extend over one screen page can be captured by Screen capture programs for editing/printing. Many Screen Capture programs now have auto-scroll window to capture long documents or web pages. They are downloadable free from the web for trial use and cost between $10 to $40. Examples are: ScreenPrint, SD Capture, Any Capture, Mr Captor, SuperCapture, SnagIt, Hyper Snap-DX.
2. Printing The Data Forms:   To print the Input and Output forms, simply use the print feature of your web browser. Select any of the frame printing options. Note that graph/charts will not be printed when you use the browser print facility.
3. Printing Graphs:   To print a graph/chart display, make a "screen shot" of the graph and paste it on an application/graphics program. Then you can edit or save it to a file in different formats. The screen shot is also called a "screen capture" or "screen dump". If you can make screen captures and know how to use standard graphics software, then you should be able to use Peteng images in figures, slides, emails etc. Mac and Windows computers come with screen capture support.
4. Printing Graphs On PCs:   If you are running Microsoft Windows95 => WindowsNT, you can capture an image of your screen using the "print screen" (PRINT SCREEN) key. (For details, look up "screen capture" under the Windows Help.) To make a "screen shot":
   Press ALT+PRINT SCREEN (grabs image of active window) or PRINT SCREEN (grabs image of entire screen.)
   Open up any program that can read bitmapped images (eg. graphics programs like Photoshop, Microsoft applications like MS-Word, MS-Paint, Screen capture programs like SnagIt, ScreenPrint, etc).
   Use the program's "paste" menu option to paste in the screen shot image. The image should appear in the graphics program window.
   Use the "crop" feature of the program erase unwanted portions of the image. Then you can "resize" the image proportionately from the center outward. In Word, you perform this resize task by holding down CTRL+SHIFT and drag a corner sizing handle.
   Save the image or document file.

Happy calculating !