DPGraph Documentation |

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**After you have downloaded and installed either the full version of DPGraph or the free DPGraph Viewer** you can click on the thumbnail
pictures to view and manipulate the graphs.
**If your version of DPGraph or
the DPGraph Viewer can't display a graph** then you may need to update to the most recent version.
To view the commands that created
the graphs, click on Edit inside DPGraph or the Viewer. **Some versions of
Netscape require you to stop and restart your browser after installing.**

**New!** French translations of some of the DPGraph documention, by
Laurent Hivon. The files are in pdf format: DPGraph Online
Help (in French), by Laurent Hivon and the DPGraph
Parametric Graphing Examples (in French), by Laurent Hivon.

**Click here for the documentation on
parametric curves and surfaces, including examples.** Information on
creating implicit and vector graphs is below. There are also hundreds of
examples in the gallery, and hundreds of examples are included with DPGraph and
the DPGraph Viewer.

**FOLLOWING IS A COPY OF THE ONLINE HELP AVAILABLE INSIDE DPGRAPH.**

Dynamic Photorealistic Graphing (DPGraph) -- the world's most powerful 2D through 8D graphing software, optimized for the internet.

Version 2013.09.05. Visit www.dpgraph.com for the full documentation, or click on Open and then Edit to examine the sample files for useful tips; this online help is a summary. Copying DPGraph for unlicensed users is illegal. DPGraph is a trademark of David Parker. Other company and products names are trademarks or registered trademarks of their respective companies. Copyright (C) 1997-2013 by David Parker. All rights reserved.

**COMMON ERRORS:** The seven most common mistakes when creating graphs in
the EDIT dialog box are: 1) leaving out asterisks for multiplication; 2)
leaving out equals signs or inequality signs; 3) leaving out the parentheses for
lists; 4) trying to use equalities in intersections (DPGraph can only intersect
inequalities, i.e. regions of space); and 5) putting a space inside the
two-character symbols :=, >=, or <=;
6) using the parametric variables u or v in implicit graphs; and
7) using the implicit variables x, y, z, r, theta, rho, or phi in parametric graphs.

Wrong: | Right: | |

`graph3d( 3x = z^2 )` | `graph3d( 3*x = z^2 )` | |

`graph3d( x^2+y^2 )` | `graph3d( z = x^2+y^2 )` | |

`graph3d( x=1, y=1 )` | `graph3d( ( x=1, y=1 ) )` | |

`graph3d( x=1 & y=1 )` | `graph3d( x>1 & y>=1 )` | |

`graph3d( z^2> =x^2 )` | `graph3d( z^2 >= x^2 )` | |

`graph3d( z=u^2+v^2 )` | `graph3d( z=x^2+y^2 )` | |

`graph3d( rectangular(x,y,sin(x+y)) )` | `graph3d( rectangular(u,v,sin(u+v)) )` |

**INEQUALITIES:** When graphing an inequality, such as GRAPH3D( X>1 ),
remember that "blue is true"; the bluest side of the graph is the region of
space for which the inequality is true, the reddest side of the graph is the
region of space for which the inequality is false. If the inequality is true
for the surface itself, as in GRAPH3D( X>=1 ), then the bluest side is pure
blue; if the inequality is false for the surface itself, as in GRAPH3D( X>1
), then the reddest side is pure red.

**DEFAULTS.DPG:** With experience you may find the following technique
useful when exploring a new surface. OPEN the file DEFAULTS.DPG, go to EDIT,
modify the default equation, and then EXECUTE. Since all of the options are
already in DEFAULTS.DPG they can be changed with very little typing. If you
like, SAVE the modified file under a different name and it will be ready for
future viewing and adjustments.

**RESOLUTION:** The easiest way to improve the appearance of some graphs
is to increase the resolution. The default resolution is 21 by 21 by 21 for implicit graphs, and 40 by 40 for parametric surfaces. To
change the resolution for implicit graphs, use the EDIT dialog box to insert a line such as the
following before the GRAPH3D command:

graph3d.resolution := 30

For parametric surfaces:

graph3d.stepu := 50 graph3d.stepsv := 50

You may find it useful to use the technique described in the previous section on DEFAULTS.DPG.

**COPYING A GRAPH TO THE CLIPBOARD:** Click on CLIPBOARD to copy a
picture of the graph to the clipboard. To copy a picture of the entire window
(including the border, etc.) to the clipboard, simultaneously press down the ALT
and PRINTSCREEN keys. To copy a picture of the whole screen to the clipboard,
press PRINTSCREEN.

**COPYING A GRAPH INTO ANOTHER APPLICATION:** If the other application
supports pasting, first copy the graph to the clipboard. Then click on EDIT in
the other application, then click on PASTE.

**PRINTING A GRAPH:** First copy the the graph to an application, such as
Word or Paint, that supports printing. Then click on FILE in the other
application, then click on PRINT.

**FILE FORMAT:** DPGraph files have a file type of .DPG. There are two
kinds of DPG files: binary and ASCII. DPGraph can read and write
either type of DPG file, but the DPGraph Viewer can only read binary
DPG files.
Binary DPG files are
compressed and contain error detection information for more reliable
transmission. ASCII DPG files are readable and editable by Notepad and many other
text editors. Each line in the file is a separate command for
DPGraph. For example, a file might look like this:

graph3d.view:=top graph3d.perspective:=false graph3d(z=3*sin(x*y))

Each command must start on a separate line. The GRAPH3D command must be the last command.

**UNINSTALLATION:** There are two ways to remove DPGraph from your
hard disk drive. Method 1: click on START - SETTINGS - CONTROL PANEL -
ADD/REMOVE PROGRAMS, then scroll to DPGraph in the window, select it, and
click on ADD/REMOVE. Method 2: click on START - PROGRAMS - DPGRAPH -
UNINSTALL.

**OPTIONS:** Non-numeric default values are given in capital
letters.

`graph3d.resolution` | (resolution along longest side of box, default is 21; other sides of box have a resolution proportional to the length of the side) |

`graph3d.mesh` | (TRUE or false) |

`graph3d.perspective` | (TRUE or false) |

`graph3d.box` | (TRUE or false) |

`graph3d.view` | (STANDARD, top, side, front, or textbook) |

`graph3d.contrast` | (default is 1/2, range is 0 to 1) |

`graph3d.transparency` | (default is 0, range is 0 to 1) |

`graph3d.background` | (black, gray, WHITE, brown, red, yellow, green, cyan, blue, or magenta) |

`graph3d.color` | (BYHEIGHT, bysteepness, black, gray, white, brown, red, yellow, green, cyan, blue, magenta, or an expression depending on x, y, z, or time) |

`graph3d.highlight` | (default is 0, range is 0 to 1) |

`graph3d.shading` | (default is 0, range is 0 to 1) |

`graph3d.vectorcolor` | (BYHEIGHT, bysteepness, black, gray, white, brown, red, yellow, green, cyan, blue, magenta, or an expression depending on x, y, z, or time) |

`graph3d.vectorhighlight` | (default is 0, range is 0 to 1) |

`graph3d.vectorshading` | (default is 0, range is 0 to 1) |

`graph3d.vectoralign` | (TAIL, center, or tip) |

`graph3d.vectorarrowhead` | (true or FALSE) |

`graph3d.minimumx` | (default is -3) |

`graph3d.maximumx` | (default is 3) |

`graph3d.minimumy` | (default is -3) |

`graph3d.maximumy` | (default is 3) |

`graph3d.minimumz` | (default is -3) |

`graph3d.maximumz` | (default is 3) |

`graph3d.minimumu` | (default is -3) |

`graph3d.maximumu` | (default is 3) |

`graph3d.stepsu` | (default is 40) |

`graph3d.minimumv` | (default is -3) |

`graph3d.maximumv` | (default is 3) |

`graph3d.stepsv` | (default is 40) |

`a.minimum` | (scrollbar variable minimum value) |

`a.maximum` | (scrollbar variable maximum value) |

`b.minimum` | (scrollbar variable minimum value) |

`b.maximum` | (scrollbar variable maximum value) |

`c.minimum` | (scrollbar variable minimum value) |

`c.maximum` | (scrollbar variable maximum value) |

`d.minimum` | (scrollbar variable minimum value) |

`d.maximum` | (scrollbar variable maximum value) |

**VALUES FOR OPTIONS:**

`true` | (for mesh, perspective, box, and vectorarrowhead) |

`false` | (for mesh, perspective, box, and vectorarrowhead) |

`standard` | (for view, x is the most horizontal axis) |

`textbook` | (for view, y is the most horizontal axis) |

`top` | (for view) |

`front` | (for view) |

`side` | (for view) |

`byheight` | (for color or vectorcolor) |

`bysteepness` | (for color or vectorcolor) |

`black` | (for color, vectorcolor, or background) |

`gray` | (for color, vectorcolor, or background) |

`white` | (for color, vectorcolor, or background) |

`brown` | (for color, vectorcolor, or background) |

`red` | (for color, vectorcolor, or background) |

`yellow` | (for color, vectorcolor, or background) |

`green` | (for color, vectorcolor, or background) |

`cyan` | (for color, vectorcolor, or background) |

`blue` | (for color, vectorcolor, or background) |

`magenta` | (for color, vectorcolor, or background) |

`tail` | (for vectoralign) |

`center` | (for vectoralign) |

`tip` | (for vectoralign) |

**CONSTANTS:**

`e` | (base of natural logarithms) |

`#e` | (base of natural logarithms for Derive users) |

`pi` | (pi) |

**VARIABLES:**

`x` | (x variable for implicit graphing) |

`y` | (y variable for implicit graphing) |

`z` | (z variable for implicit graphing) |

`r` | (polar radius, r=sqrt(x^2+y^2)) |

`theta` | (polar angle, 0<=theta<2*pi, theta=angle(-x,-y)+pi) |

`rho` | (spherical radius, rho=sqrt(x^2+y^2+z^2)) |

`phi` | (spherical angle, 0<=phi<=pi, phi=angle(z,r)) |

`u` | (u variable for parametric graphs) |

`v` | (v variable for parametric graphs) |

`a` | (a variable for scrollbar) |

`b` | (b variable for scrollbar) |

`c` | (c variable for scrollbar) |

`d` | (d variable for scrollbar) |

`time` | (current time for graphs that change with time) |

**SYMBOLS:**

`=` | (equals, for entering equations) |

`<` | (less than, for entering inequalities) |

`>` | (greater than, for entering inequalities) |

`<=` | (less than or equal, for entering inequalities) |

`>=` | (greater than or equal, for entering inequalities) |

`&` | (intersection) |

`:=` | (assignment, for assigning values) |

`(...)` | (lists of arguments or equations) |

`+` | (addition or leading plus sign) |

`-` | (subtraction or leading minus sign) |

`*` | (multiplication) |

`/` | (division) |

`^` | (powers) |

`|...|` | (absolute value, same as abs(...)) |

`!` | (factorial) |

**ONE ARGUMENT FUNCTIONS:**

`abs` | (absolute value, same as |...|) |

`acos` | (arccosine) |

`acosh` | (hyperbolic arccosine) |

`acot` | (arccotangent) |

`acoth` | (hyperbolic arccotangent) |

`acsc` | (arccosecant) |

`acsch` | (hyperbolic arccosecant) |

`asec` | (arcsecant) |

`asech` | (hyperbolic arcsecant) |

`asin` | (arcsine) |

`asinh` | (hyperbolic arcsine) |

`atan` | (arctangent) |

`atanh` | (hyperbolic arctangent) |

`ceiling` | (smallest integer >= argument) |

`cos` | (cosine) |

`cosh` | (hyperbolic cosine) |

`cot` | (cotangent) |

`coth` | (hyperbolic cotangent) |

`csc` | (cosecant) |

`csch` | (hyperbolic cosecant) |

`floor` | (greatest integer <= argument) |

`gamma` | (gamma function) |

`ln` | (log base e) |

`log` | (log base 10) |

`nonneg` | (1 if x>=0, else undefined) |

`one` | (1 if 0<=x<=1, else undefined) |

`sec` | (secant) |

`sech` | (hyperbolic secant) |

`sign` | (-1 if negative, 1 if positive, indefinite if 0 or indefinite) |

`sin` | (sine) |

`sinh` | (hyperbolic sine) |

`sqr` | (square) |

`sqrt` | (square root) |

`tan` | (tangent) |

`tanh` | (hyperbolic tangent) |

**TWO ARGUMENT FUNCTIONS:**

`angle` | (-pi <= angle of (x,y) from positive x axis <= pi) |

`beta` | (beta function) |

`max` | (maximum value) |

`min` | (minimum value) |

**THREE ARGUMENT FUNCTIONS:**

`cylindrical` | (parametric graph in cylindrical coordinates) |

`near` | (1 if (x,y,z) is near current grid, else undefined) |

`rectangular` | (parametric graph in rectangular coordinates) |

`spherical` | (parametric graph in spherical coordinates) |

`vector` | (graphs a vector field) |

**KNOWN PROBLEMS:**

- Microsoft WordPad under Windows NT 4.0 makes embedded graphs, or graphs copied from the clipboard, too large. It also truncates the graphs on the right hand side.
- Microsoft Paint in 256 color mode decreases the number of colors in the graphs to 16.

Copyright © 1997-2015 by David Parker. All rights reserved.