1.0 Introduction ---------------- This is a short walkthrough of the polydemo program, with examples of the use of all of the available commands. I am assuming that you have already looked at the header of the source code of polydemo, which describes the options available in the polydemo. When a series of commands or entries must be given, they will be listed here separated by commas. Each entry in such a list should be followed by pressing Return or Enter. Single-letter commands must always be followed with Enter as well. The case of any letter is ignored. 2.0 Preparing the polydemo program ---------------------------------- Polydemo requires the library polystuf, also included on this disk. To set up polydemo for running, first translate polystuf into ucode files with ICONT -c polystuf and then translate polydemo with ICONT polydemo after which you can run polydemo in whatever manner your system allows. 3.0 A sample run ---------------- Let's say we had to perform the following: find the result of evaluating 4 3.1 0.7 5 4 (9x + 6x + 5 - 3x ) - (12x - 4.2x + x) at x = 2.2. Start the polydemo program. A menu of options will be displayed, as will the slots that are filled (none yet) and a prompt containing valid characters corresponding to the options. Enter R to read in a polynomial from the keyboard, then give A as the slot of the first polynomial. Enter these numbers: 9, 4, 6, 3.1, 5, 0, -3, 0.7, 0. Now, the first polynomial will be stored in slot "a." Note that the 0 is necessary after the 5 to use a constant term, and that the 0 at the end is for stopping data entry. A similar process can be used for the second polynomial. Inputting R, B, 12, 5, -4.2, 4, 1, 1, 0 will place that polynomial in slot "b." Now, check to make sure you've entered the polynomials correctly. Type W for "write" and A for slot "a," to display the first polynomial on the screen. It should appear as 9x^4 + 6x^3.1 + -3x^0.7 + 5. Do the same for the second polynomial (replacing the A with a B). The output should be 12x^5 + -4.2x^4 + x. To find their difference, enter S for subtract, then A, B to indicate those two polynomials, then C as a slot for the answer. Note that the result isn't immediately displayed; you must use W, C for that. The answer should be -12x^5 + 13.2x^4 + 6x^3.1 + -x + -3x^0.7 + 5. Finally, to evaluate this polynomial at x = 2.2, type E for evaluate, C for the slot in which that polynomial is held, then 2.2 for the x-value. You should receive the message "The result is -242.498468213815," or something similar, depending on the precision of real numbers in your implementation of Icon. The Add and Multiply commands are invoked similarly to the Subtract command. The Clear option allows you to empty a slot, making room for a new polynomial. This is necessary because you cannot overwrite an existing polynomial. Asking for Help displays the list of options and the letters needed to access them. Lastly, using Quit exits the program. It would be good to test operations in which one or both polynomials are zero. A zero polynomial is made when, during entry, a 0 is the first and only coefficient given, or when it is the result of an operation. Also, to make sure no "1x", "-1x" or "x^1" appears in a written polynomial (these should be "x", "-x", and "x," respectively), try working with polynomials that have these terms.