DETAILS OF THE R-TEK SCRATCHPAD This text file provides a much more detailed description of the capabilities of the R-Tek Scratchpad (version 1.08) than is possible in the descriptive text accompanying the upload. Minimum System Requirements (it is recommended to exceed these minimums) Windows 3.1, 386 processor, 4Mb RAM, 4Mb free hard disk space, VGA color, mouse Keywords windows, mathematics, statistics, scientific, scratchpad, calculator, graph, plot, polar, programming, fraction, mixed number, trigonometry, matrix, linear algebra, finance, linear programming What the R-Tek Scratchpad does: The scratchpad is best thought of as a full-featured printing, graphing, scientific scratchpad calculator. A "scratchpad" calculator is a cross between a calculator and a word processor that allows you to enter and work with mathematical expressions using booklike expression formatting (ie, the expressions you view on screen (or print) look a lot like you would write them on a sheet of paper, not some cryptic programming command line). Scratchpad calculations are essentially self documenting, but you can also add comments to your work, thereby providing an aid to understanding for someone (perhaps even yourself ) who examines your solution later. The scratchpad has built-in functions to enable you to handle a great variety of math problems (see Keywords above). It was written to provide an ideal environment for undergraduates in finite mathematics, linear algebra, and statistics courses to explore the problems in their texts. The key to mastering these subjects, as in many others, is to work problems - the more the better. This program can eliminate much of the drudgery of hand calculations, saving time that can be better spent solving more problems, as well as document your solutions in a very readable format. Students in the natural and social sciences, indeed in many areas of study other than math and statistics will also find the scratchpad's built-in capabilities to be very useful. The advanced high school student wishing to explore on his own might find an Intro to Finite Math textbook an easier read than the typical calculus text and at the same time, a very enjoyable read because of the wide range of topics covered. The scratchpad has a simple programming language which is not required for simple calculations in the scratchpad, but does allow the interested student to learn programming fundamentals. It has an autosubstitution capability that allows generation of random example problems. Besides extensive on-line help, context sensitive help is provided for quick function reference. The right mouse button allows quick access to object characteristics. The scratchpad comes withs a number of example files that demonstrate some of its many powerful capabilities. In short, the scratchpad has so many powerful features that few individuals will master them all, but is well worth the small registration fee (less than most video games) even if you intend using it for nothing more than simple calculations involving fractions and mixed numbers. (Its like having an advanced scientific calculator where you don't know what all the buttons are for. You can still use it effectively on problems that interest you by using the buttons that you do know!) What the R-Tek Scratchpad does not do: Written with the student in mind, the R-Tek Scratchpad is not suitable for working with systems of equations involving thousands of variables. It does not solve equations symbolically, automatically handle units, draw 3-D graphs, or communicate with other programs. It can numerically calculate simple integrals and derivatives, but does not handle differential equations and advanced calculus. Users needing these capabilities would be better served by a package targeting professionals. DETAILED DESCRIPTION: Graphs - quick & easy, just create, fill in the blanks, size and run. Multitrace, function or matrix plots (with quick & easy cartesian/polar conversion) Cartesian (can be log or log/log) Polar Data Types Booleans (logicals) Numbers integers (which can be very big) rationals(fractions) Calculations involving rationals with large integers for numerator and denominator are "exact" calculations. Besides the obvious ability to work with large integers (eg 500 factorial), for some problems "exact" calculations can eliminate problems associated with matrix "ill-conditioning", since "exact" inverses are calculable. mixed numbers(whole+fraction) reals(decimals) imaginaries(multiples of the square root of -1) complex (real+imaginary) Matrices (vectors) Programming Commands (not required for simple calculations) proc return endproc if else endif matloop endmatloop while endwhile break continue comments endcomments autosubblock endautosubblock autosub endautosub show hide Predefined Constants pi e i (j) true false TOL Greek Alphabet type Ctrl+g followed by Roman equivalent, or simply click on the Greek letter on the second Toolbar Numeric (or hot key) Operators assignment exchange +, -, *, /, ^ (remember that the expression rearranges to look like you would write it on a sheet of paper) square root factorial percent complex conjugate absolute value derivative integral iterated sum iterated product permutations combinations Logical Operators (these operators also look like you would write them on a sheet of paper) assignment and or not equal to not equal to less than not less than greater than not greater than less than or equal to not less than or equal to greater than or equal to not greater than or equal to Matrix Operators assignment exchange +, -, *, ^ (inverse) determinant complex conjugate transpose augment matrix element row vector extraction column vector extraction Vector Specific Operators dot product cross product Numeric Functions Numeric Property least common multiple greatest common divisor integer divide modulus ceiling (next larger integer) floor (next smaller integer) integer part fractional part numerator denominator real part imaginary part argument (angle in complex plane) Trigonometric Functions sin cos tan sec csc cot asin acos atan Hyperbolic Trigonometric Functions sinh cosh tanh sech csch coth asinh acosh atanh Logarithms ln log Small Primes (less than 100,000,000) is small prime small prime factorization previous small prime next small prime Random Number Generator randomize random normal deviate random (depending on argument, can return any of the numeric types) random exclude functions (exclude zero, zero and one, or integers) Miscellaneous Newton-Ralphson root polishing if Heaviside Step Function Kronecker Delta completely antisymmetric tensor (rank 3) derivative integral (hot keys) iterated sum (hot keys, uses standard Greek iterated product sigma or pi notation) Matrix Functions Creation zero matrix identity matrix sub matrix extraction sub vector extraction display matrix (user fills in matrix elements) diagonal (creation or extraction) ones vector Random Matrix Creation random data using normal deviate random creation and filling with a numeric type random exclude functions (exclude zero, zero and one, integers, singular matrices, singular matrices with zero, zero and one, or integers) Matrix Property rows columns max min sum mean variance standard deviation trace Sorting reverse order of rows sort vector sort matrix columns depending on elements of particular row sort matrix rows depending on elements of particular column Equation Solving Aids rank minor adjoint Gauss-Jordan pivot echelon form echelon transformation matrix particular solution homogeneous solution singular value decomposition (multi-function) eigenvalues and eigenvectors Gram-Schmidt orthonormalization Interpolation and Extrapolation linear interpolation spline functions (linear, parabolic, and cubic) matrix interpolation (using spline results) single point interpolation (using spline results) Curve Fitting slope and intercept regression analysis (calculate ANOVA matrix, confidence intervals for beta, confidence intervals for predicted y) Statistical Functions General histogram permutations (hot keys, uses common combinations subscripted P or C notation) gamma function incomplete gamma function natural logarithm of the gamma function error function ANOVA one way ANOVA two way ANOVA two way ANOVA with interaction Rank Statistics statistically rank a matrix Wilcoxon rank sum Mann-Whitney sign test Wilcoxon signed rank Kruskal-Wallis number of runs Friedman Spearman's rank correlation Statistical Distributions There are in general three related functions for each distribution provided in the scratchpad. (These functions should eliminate much of the need to search through distribution tables in textbook appendices.) 1. Calculates the value of the distribution function at a specified x, z, t, etc. 2. Calculates the cumulative value of the distribution function up to a specified x, z, t, etc. 3. Calculates the particular value of x, z, t, etc. that corresponds to a specific cumulative value of the distribution function (eg, 0.95, 0.99, etc.). Distributions provided: Binomial Geometric Hypergeometric Exponential Normal Chi-Square - there are two addition functions in the scratchpad that calculate the chi-square values of contingency tables F Poisson Student-t Kolmogorov-Smirnov Financial Functions Five value problems - many financial problems involve five interdependent variables: present value, future value, number of payment periods, interest per payment period, and the payment amount. By supplying 4 of these five, this function solves for the fifth. Interest on payment range for a five value problem Principal on payment range for a five value problem EFF to APR APR to EFF Linear Programming maximize an objective function subject to constraints minimize an objective function subject to constraints Fast Fourier Transforms transform inverse transform I tried to show an example of each function's use (although I did not often use real world data) so I think you will find that a careful study of the many example files (perhaps coupled with some cut and paste) will provide you with a good foundation for exploring on your own with the R-Tek Scratchpad. Registration Fees (version 1.08) $15 US - see orderfrm.wri using Windows Write or Wordpad for additional details. Registered users will receive the current version of the R-Tek Scratchpad on a 3.5" HD diskette that will include a key file to remove the nuisance registration incentives. The key file will continue to function with any maintenance updates to the scratchpad until its next major revision. Registered users will also receive a quick reference guide to the scratchpad (a 36 page booklet). Thank you for your consideration of the R-Tek Scratchpad! Walter C. Riley