GDF Plotter  Mathematical grapher 
GDF is a freeware program that allows you to draw any single variable mathematical function, circumferences, ellipses, parabolas, hyperbolas and sheaves of functions on a Cartesian coordinate system.
For more information please refer to detail section in this page.
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Graph functions, circumferences, ellipses, parabolas, hyperbolas and function families.
Automatic scan relative maximum and minimum on a graph providing 15 digit precision float values.
Show a
tendency icon (increasing/decreasing) when traversing graphics.
Defining or editing a graphic is easy by means of the Edition Object window as
shown below. You just click type of graph you want to create or edit
and fill the form specifying value such as the coordinate for the focus, center, etc. It assumes you're familiarized with descriptive
geometry concepts and curves definition.
In order to insert functions such as 'log','exp', etc, while editing, you can select part of the text of the equation using the mouse and click on the builtin function you want to apply it, using the 'insert' menu. In example, if you wrote x^2+x+1 and want to get x^2+log (x+1): you must paint "x+1" form first equation and click 'logarithm' from insert menu.
Functions 
Operators 

abs  Absolute value  !  Factorial 
atn  Arctangent  ^  Power 
cos  Cosine  *  Multiply 
exp  Powered number 'e'  /  Division 
gamma  Gamma function  \  Integer División (result will be truncated) 
inv  Inverse    Substract 
ln  Napierian Logarithm  +  Add 
lngamma  Napierian Logarithm of function gamma  Note: All trigonometric functions works with decimal grades.. 

log  Logarithm base 10  
sqrt  Squared root  
trpl  Triple root 

sin  Sine  
sgn  Sign  
tan  Tangent 
License statusPermission enabledPermission for users to run this software is updated every month. For more information please check the licence of the product. 
Donate 5€ to support the author on improving and mainteining this free software. 