Plot starts at 1

Hello everyone,

I have a plot what starts at one instead of zero.

Can someone tell me were my fail is?

  B=app.BEditField.Value;
            C=app.CEditField.Value;
            D=app.DEditField.Value;
            E=app.EEditField.Value;
            x = linspace(0,pi,100);
            y=D*sin(C*atan(B*x-E*(B*x-atan(B*x))));
            plot(app.UIAxes,y);
            app.UIAxes.YLim = [-0.2 (D+0.2)];
            app.UIAxes.XLim = [-10 100];

Answer 1

[Stephane Dauvillier]

Hi you should use x and y in the plot command:

plot(app.UIAxes,x,y)

[Benedikt Schumacher]

Hi if I plot it with X the course of the course isn't right. If I plot without x the course is the right one, but only starts at 1. I attached you the pictures. Thank you for your help.

[Voss]

Try plotting with x and y and setting the XLim appropriately:

x = linspace(0,pi,100);
y=D*sin(C*atan(B*x-E*(B*x-atan(B*x))));
plot(app.UIAxes,x,y);
app.UIAxes.YLim = [-0.2 (D+0.2)];
app.UIAxes.XLim = [0 pi];

[Steven Lord]

That is correct. For an explanation, from the Description section on the plot documentation page:

"plot(Y) plots Y against an implicit set of x-coordinates.

• If Y is a vector, the x-coordinates range from 1 to length(Y).
• If Y is a matrix, the plot contains one line for each column in Y. The x-coordinates range from 1 to the number of rows in Y."

In this case, app.UIAxes is not X data (which would cause MATLAB to use the plot(x, y) syntax.) It is recognized as an axes so the first syntax in Additional Options is used, then the remaining input is interpreted as Y data using the syntax above.

[Stephane Dauvillier]

your plot with x is the right one.The limits of the axes are not what you want but the data are well drawed.

ANd you can use the function below to set the limit of axes

xlim(app.UIAxes,[-10,100])
ylim(app.UIAxes,[-0.2,0.2+D])