标题：JKGRAPH
概述
JKGRAPH是和WINPLOT齐名的电脑函数绘图软件。只能做二维的，但是可以进行极值、积分计算等复杂的分析方法。
  文件图标
英文帮助文件
The programThe program called JKGRAPH is a Microsoft WINDOWS program for graphing and
analyzing graphs of various kinds of functions that students are likely to
encounter in a math class.  It is also a useful tool for teachers to create
graphs that can be imported into WINDOWS word processing documents.  The
math level ranges from precalculus through the first year of calculus.  An
overview of the program's capabilities is included in this file following the
descriptions of the distributed files.
THE DISTRIBUTED FILES=====================
The following describe the contents of the file JKGRAPH.ZIP which contains
the distribution files for the program named JKGRAPH.
Filename        Description
-----------     --------------------------------------------------------------
JKGRAPH.EXE     This is the executable file that is the JKGRAPH program.
JKGRAPH.HLP     This is the WINDOWS on-line help file for JKGRAPH.
JKGRAPH.ICO     This is the icon file for the JKGRAPH program.
JKGTUT .WRI     This is a tutorial file in Microsoft WRITE format.
HELP   .TXT     This is the text file you are now reading.
You should at least read the document file JKGTUT.WRI before running the
JKGRAPH program for the first time.  In fact, it is best to simply print
the file JKGTUT.WRI so you can read from the paper copy while you view the
output on your computer screen.  JKGTUT.WRI is a tutorial file that takes
you through the beginning steps of using the program.  It is especially
useful for first-time users of the program.  JKGTUT.WRI is in the Microsoft
WRITE format which is the word processor that accompanies WINDOWS 3.1.  If
you have WINDOWS 95 you can also print this document using the program called
WORDPAD that replaces Microsoft WRITE.  In fact, you should be able to import
the file JKGTUT.WRI into any word processor that imports Microsoft WRITE
files.  Microsoft WORD for WINDOWS can also import this file.
Another source of information is the WINDOWS on-line help file for JKGRAPH.
This help file contains an overview of the program as well as detailed
sections on all the menu items and all the dialog boxes.  It also has a list
of special topics.
JKGRAPH Version 1.0 is a fully functioning program except for the features
using WINDOWS Metafiles because Microsoft has changed the Metafile format to
a new format that is in WINDOWS 95 called Enhanced Metafiles.  As soon as
this file format is fully supported in Borland's DELPHI compiler a newer
version of JKGRAPH will be released.  The new version may not be available
until early 1996, but at least you can expect that enhanced metafiles will
be supported at some time in the future.  The next version will probably also
be specifically written for WINDOWS 95.
JKGRAPH OVERVIEW================
The program called JKGRAPH is used to graph and analyze 2-dimensional
function curves.  By a function curve we mean any graph that can be made
using standard rectangular functions or polar function curves or any other
curve given in a parametric form.  Thus we use the term function as a synonym
for any 2D curve that can be described using piecewise continuous formulas.
Curves such as ellipses, hyperbolas and cardioids  may not be functions
according to the strict mathematical definition of a function.  We allow an
x-coordinate to determine more than one y-coordinate.  The next few paragraphs
outline the operations you can perform on various function curves and serve
as a summary of the capabilities of the JKGRAPH program.
JKGRAPH uses four distinct function groups which include standard rectangular
functions in the form Y=F(X), polar functions in the form R=F(@), parametric
functions in the form X=F(T) and Y=G(T), and polar parametrized functions in
the form R=F(T) and @=G(T).  Note that we use the variable T for time in
parametric formulas.  We also use the special character @ to represent any
angle associated with polar coordinates.  Think of using @ for angles because
this is the ASCII character symbol that comes closest to matching any of the
Greek letters alpha, or phi, or theta that would normally be used to denote
angles.
The graphics features of JKGRAPH are quite general.  You can view any
rectangular portion of the XY-plane and you can easily perform zooming
operations.  You can control individual graph curve attributes which include
colors and line thickness.  You can also select from among 8 different
background grids which include combinations of the standard XY-axes,
polar-coordinate axes, and an XY-lattice line-grid.  All the background
elements may be scaled and colored to change their appearance.  You can also
select colors for any filled region, including the entire graph background.
You can copy any graph to the clipboard in a color bitmap format in which you
specify both the size of the graph in inches and the resolution in terms of
the number of pixels per inch.  Thus JKGRAPH can be used to make color graphs
that can be imported into other Windows applications.  In particular, JKGRAPH
makes it a breeze to create graphs and other tables that can be incorporated
into the scientific word processor called EXP.  This is one of the major
reasons why the author of JKGRAPH decided to write the program.
Within each function group you can work with two independent curves or you
can link the two curves and then perform special operations such as finding
points of intersection or integrating to find the area between two curves.
Once a curve (or curves) have been entered you can analyze the curves.
JKGRAPH provides four trace modes with the names Coordinate Trace Mode, Graph
Trace Mode, Tangent Line Trace Mode, and Normal Line Trace Mode.  In each
mode you can drag the mouse cursor across the screen and dynamically see
graphic elements and other information related to the trace position.
JKGRAPH can also perform special animated actions on function curves.
Included are operations for automatically finding maxima and minima points on
a curve or automatically finding multiple intersection points between two
curves.  These features operate on all four function groups including polar
and parametrized curves.
For ordinary Y=F(X) function curves you can apply either Newtons Method or
the Method of Successive Bisections to find the x-intercepts.  Both of these
methods can show an animated action and can create tables of values that are
generated during the processes.  The table information is easily copied to
the Windows clipboard
You can also apply several integration techniques to any curve.  For
rectangular functions there are 11 different integration techniques which
include lower, upper and midpoint Riemann sums, the Trapezoid Rule, Simpson's
Rule, Gaussian Quadrature, the Romberg Algorithm, arc length and surface area
and volumes using either disks or washers or cylindrical shells.  For polar
and parametric function types you can calculate areas and arc length.
JKGRAPH can also automatically graph the derivative or inverse of any
function curve.
界面情况
  如图为函数示范如图，为函数x*sinx的图形，以及积分情况。