Documentation |
Function calculator
funtool
funtool is a visual function calculator that manipulates and displays functions of one variable. At the click of a button, for example, funtool draws a graph representing the sum, product, difference, or ratio of two functions that you specify. funtool includes a function memory that allows you to store functions for later retrieval.
At startup, funtool displays graphs of a pair of functions, f(x) = x and g(x) = 1. The graphs plot the functions over the domain [-2*pi, 2*pi]. funtool also displays a control panel that lets you save, retrieve, redefine, combine, and transform f and g.
The top of the control panel contains a group of editable text fields.
f= | Displays a symbolic expression representing f. Edit this field to redefine f. |
g= | Displays a symbolic expression representing g. Edit this field to redefine g. |
x= | Displays the domain used to plot f and g. Edit this field to specify a different domain. |
a= | Displays a constant factor used to modify f (see button descriptions in the next section). Edit this field to change the value of the constant factor. |
funtool redraws f and g to reflect any changes you make to the contents of the control panel's text fields.
The bottom part of the control panel contains an array of buttons that transform f and perform other operations.
The first row of control buttons replaces f with various transformations of f.
df/dx | Derivative of f |
int f | Integral of f |
simplify f | Simplified form of f, if possible |
num f | Numerator of f |
den f | Denominator of f |
1/f | Reciprocal of f |
finv | Inverse of f |
The operators int f and finv can fail if the corresponding symbolic expressions do not exist in closed form.
The second row of buttons translates and scales f and the domain of f by a constant factor. To specify the factor, enter its value in the field labeled a= on the calculator control panel. The operations are
f+a | Replaces f(x) by f(x) + a. |
f-a | Replaces f(x) by f(x) - a. |
f*a | Replaces f(x) by f(x) * a. |
f/a | Replaces f(x) by f(x) / a. |
f^a | Replaces f(x) by f(x) ^ a. |
f(x+a) | Replaces f(x) by f(x + a). |
f(x*a) | Replaces f(x) by f(x * a). |
The first four buttons of the third row replace f with a combination of f and g.
f+g | Replaces f(x) by f(x) + g(x). |
f-g | Replaces f(x) by f(x)-g(x). |
f*g | Replaces f(x) by f(x) * g(x). |
f/g | Replaces f(x) by f(x) / g(x). |
The remaining buttons on the third row interchange f and g.
g=f | Replaces g with f. |
swap | Replaces f with g and g with f. |
The first three buttons in the fourth row allow you to store and retrieve functions from the calculator's function memory.
Insert | Adds f to the end of the list of stored functions. |
Cycle | Replaces f with the next item on the function list. |
Delete | Deletes f from the list of stored functions. |
The other four buttons on the fourth row perform miscellaneous functions:
Reset | Resets the calculator to its initial state. |
Help | Displays the online help for the calculator. |
Demo | Runs a short demo of the calculator. |
Close | Closes the calculator's windows. |