Frequently Asked Questions

Q: What are the system requirements of Graph?
A: Graph requires Microsoft Windows 2000 or newer. It has been tested under Windows 2000, Windows XP, Windows Vista, and Windows 7.
Q: Will Graph run under Linux?
A: Graph is a native Windows application and not tested under Linux, but several users have informed me that Graph runs without problems under Linux with Wine.
Q: Will Graph run on a Mac?
A: As with the above, you cannot run Graph directly on a Mac. However a bundle of Graph with Wine is available.
Q: When will the next version be released?
A: When it is ready.
Q: How can I move the coordinate system?
A: When you hold down the Ctrl key you can use the arrow keys to move the coordinate system.
You can also use ZoomMove system and drag the coordinate system around with the mouse.
Q: How can I easily zoom in and out?
A: When you hold down the Ctrl key you can use the + and - keys to zoom in and out.
The scroll wheel on the mouse can be used for zooming at the position of the mouse pointer.
When you move the scroll wheel up, Graph will zoom into the coordinate system and center the graphing area at the position of the mouse pointer.
When you move the scroll wheel down, Graph zooms out.
Q: How do I save default settings?
A: Set the desired default settings in the Edit axes dialog,
and check Save as default before pressing the OK button.
Next time you create a new coordinate system, the saved default settings will be used.
Q: Can I make the program remember the size and position of the window?
A: When you select Save workspace on exit in the Options dialog,
Graph will save the position and size of the main window when it quits.
The next time Graph is run, the same size and position is used.
Q: Why does the program not accept a comma as decimals separator?
A: I know a lot of countries use comma to separate the decimal part from the integer part, but Graph uses comma for separating function arguments.
The program always uses a period to separate decimals from the integer value, no matter your local settings.
Q: How do I plot a vertical line?
A: A vertical line can be drawn as a parametric function.
Select Parametric function as Function type when adding the function.
You can then add the vertical line at x=5 as x(t)=5, y(t)=t.
Alternatively you can add x=5 as a relation.
Q: How do I plot a function x=f(y)?
A: To draw a function with y as the independent variable, you need to use a parametric function.
Select Parametric function as Function type when adding the function.
If you want to draw the function x=sin(y), you can now enter the function as x(t)=sin(t), y(t)=t.
Alternatively you can draw it as a relation in which you can enter x=sin(y) directly.
Q: How do I plot a circle?
A: You need to use a parametric function to draw a circle.
When inserting the function, select Parametric function as Function type.
You can now add a circle with radius 5 and center in (2,3) as x(t)=5cos(t)+2, y(t)=5sin(t)+3.
You may need to use ZoomSquare to make the axes equally scaled.
Else the circle may look like an ellipse.
A circle can also be added as a polar function, but only with center in (0,0).
A circle with radius 5 may be added as the polar function r(t)=5.
Alternatively you can use a relation and add the circle as (x-2)^2+(y-3)^2=5^2.
Q: Why do circles look like ellipses?
A: That is probably because the axes are not equally scaled. You can either change the size of the window until the axes scales equally or select ZoomSquare in the menu to change the y-axis to scale equal to the x-axis.
Q: How do I calculate the area between the graphs of two functions?
A: If you want to find the area between two functions f1(x)=3x and f2(x)=x^2,
the easiest way is to create a new function that equals the difference between the two functions: f(x)=f1(x)-f2(x)=3x-x^2.
You can then use CalcArea to calculate the area for a given interval.
Q: How can I draw the negative part of f(x)=sqrt(x+2)?
A: For each value x, f(x) will evaluate to at most one value.
f(x)=sqrt(x+2) will therefore only have positive values of f(x).
To plot it for negative f(x) too, you will have to create two separate functions: f(x)=sqrt(x+2) and f(x)=-sqrt(x+2).
Alternatively you can plot it as the relation: y^2=x+2.
Q: How do I plot a complex function like f(t)=e^(i*t)?
A: You probably want to show the real part on the x-axis and the imaginary part on the y-axis.
In that case you can draw the function as the parametric function x(t)=re(e^(i*t)), y(t)=im(e^(i*t)).
Notice that Calculate with complex numbers must be enabled in the Edit axes dialog.
Q: How can I make Graph plot functions with vertical asymptotes correctly?
A: Functions like f(x)=tan(x) with vertical asymptotes may not always be shown correctly.
As default Graph will evaluate the function for each pixel on the x-axis.
But if the graph has a steep slope that approaches infinite and returns between two pixels, Graph will not notice it.
To plot the function correctly you can tell Graph how many evaluations to perform.
This may be entered in the Steps field in the Insert function dialog.
A number around 100,000 will usually show the function correctly.
Q: How to create a PDF file from Graph?
A: You can choose to save as PDF in the Save as image dialog.
Q: Why will the program not run under Windows 95?
A: Graph no longer supports Windows 95. The latest version to run under Windows 95 was Graph 4.2.