I try to understand the possibilities of FPLOT and consulted the documentation (relevant phrases cited below). But I don´t understand how the step size along the X-axis, for which the Y values are then calculated, becomes automatically defined or can be manually defined.

On page 17-21 in the MATLAB R2013b Programming Fundamentals documentation it is given an example which makes use of FPLOT:

s = @(x) sin(1./x);

range = [0.01,0.1];

fplot(s,range)

In the documentation for the FPLOT function (help fplot) I then find this:

fplot(FUN,LIMS,N) with N >= 1 plots the function with a minimum of N+1 points. The default N is 1. The maximum step size is restricted to be (1/N)*(XMAX-XMIN).

[X,Y] = fplot(FUN,LIMS,...) returns X and Y such that Y = FUN(X)

NOW MY OBSERVATION: If coding the following:

s = @(x) sin(1./x);

range = [0.01,0.1];

[axisX,axisY]= plot(s,range)

then I receive for the X-axis 377 values registered. While MATLAB decided that the function should be plotted based on 377 calculated steps, I for instance would like it to become calculated in the given range in 20 steps along the X-axis and therefore tried to type:

clear axisX axisY;

[axisX,axisY]=fplot(s,range,20)

But I again receive 377 values registered, but not as expected only 20. Could you explain me, how the step size along the X-axis, for which the Y values are then calculated, becomes automatically defined or can be manually defined within/by the FPLOT syntax?