Rehman Curve Sketcher v1.1
Developed by Burhan Ateeq


         This software is developed in Visual Basic 6.0 for Windows 95 operating system. The primary purpose of this software is to provide a visual tool for viewing graphs of simple functions and polynomials of the form y=f(x) using the Computer Graphics Technology. The graphs can also be used as bitmaps. The user is to specify the polynomial using the tools provided.  It must, however, be remembered that this software is designed to handle simple functions and not complicated ones.

Installation
         To install this software follow the steps below:
            1. Copy "RehmanCS.exe" on your computer in the directory of your choice.
            2. Copy "Readme.txt" and "Readme.doc" in the same directory.
            3. To run the "RehmanCS.exe" file you need the following files to be copied in your windows\system directory.
               a. "COMDLG32.OCX"
               b. "MSSTDFMT.DLL"
               c. "RICHTX32.OCX"
            These are available from www.simtel.net/simtelnet/win95/dll . For more information contact me at burhan_ateeq@yahoo.com .
            4. Right-click on the RehmanCS.exe file icon and click "send to>desktop(create shortcut)".
            5. Double-click on the icon and the program will begin.
Aims
         As mentioned earlier this software sketches simple functions of the form y=f(x). The software is designed to help young people and students who are new to the concept of graphs.  Teachers may also find this software useful in explaining the Rectangular Coordinate system and common graphs to young students.

Start Up
        This program starts with the splash screen. Clicking anywhere in the splash screen takes the user to the Grid Settings Dialog Box.

Grid Settings
       In the Grid Settings Dialog Box the user can either accept the default values (by clicking Set Grid) or enter the values of his choice. The method of entering the settings is as follows. This program provides four different scales to be used on each axis.  These can be chosen from the options. The user, then, specifies the starting and ending X values. Curve Sketcher will sketch the curve between these two X values. It must be remembered that by changing the scale the range of X values changes. The label below the options specifies the new range. When done click Set Grid.

The Equation
        Curve sketcher inputs equation of the form 
Y=a(fx)+b(gx)+c(hx)+.
Where a, b and c are coefficients of the terms and fx, gx and hx are terms in x of the form x^a or trigonometric or logarithmic terms. 
The user first specifies the coefficient of the term, and then the term using the command buttons provided. For example, if the user wants to input the equation
Y=2(x^3)+3(x^2)-5x+9
The first coefficient to be entered is 2, followed by clicking x^3 . Before the next term the operator must be entered by clicking the appropriate button + or - (in this case +). Then 3 is entered as coefficient followed by  x^2. The operator to be entered now is - (minus sign). The next coefficient is 5 and the term is x. The operator, now, is the +(plus sign). Finally, the constant term has to be entered by clicking x^a and setting the value of "a" to Zero (0).
In the same way the user can enter trigonometric and logarithmic functions.
The text box at the top displays the progress of the equation as you enter terms.
         There, however, is no room for a mistake. If you make one you will have to restart by choosing New Curve from the file menu. Curve Sketcher can take a maximum of 10 terms. Any terms entered after the tenth term will be ignored. After entering each complete term the graph can be viewed by clicking Sketch Curve.

The graph
        For each scale there is a range of values of y for which the graph will be displayed. 
When the range of x is -36 to 36 the range of y is -27 to 27.
When the range of x is -18 to 18 the range of y is -13 to 13.
When the range of x is -9 to 9 the range of y is -6.5 to 6.5.
When the range of x is -4.5 to 4.5 the range of y is --3 to 3.
Any values of "y" falling beyond the range of the current scale will not be displayed on the graph because they are out of the boundaries of the grid.

Using the curve as Bitmap
        Curve Sketcher provides you the option of saving the sketches as bitmaps and of copying them to clipboard. Simply sketch a curve and in the curve Dialog Box and click Copy to Clipboard or Save as Bitmap as appropriate.


Display Settings
         The software is designed for 800 by 600 pixel resolution. It will work for higher or lower resolutions but it works best under this resolution. The colors must be set to, at least, 16 bit (High Color).

Sketching more than one curve on the same grid
         To sketch more than one graph on the same grid sketch the first graph. Now, choose the Curve Sketcher tab in the taskbar. Enter the second equation and click sketch curve.  Choose Curve Sketcher in the taskbar and enter the third equation and so on. Curve Sketcher will sketch the equation present in the Equation box whenever the sketch curve button is clicked. The range entered for the first curve will continue for the rest.
If, however, the user wants to start with a new curve he will have to click Reset Curve Sketcher or choose New curve from the File menu.

General Curves
         You sometimes need to sketch curves of common functions such as the trigonometric or logarithmic or functions in certain specific indices of x. You need not construct the equation in those cases. Rehman Curve Sketcher provides you the facility to draw these curves at a single click. Just choose the appropriate curve from the General Curves menu.

I hope you enjoy using this software. Thank you,
Burhan Ateeq
Email:burhan_ateeq@yahoo.com
Homepage:www.geocities.com/burhan_ateeq
