fplot command what is the default resolution ?

lets say i have this code :

clc; clear all; 
close all;
 x=0:0.1:5;
 f='3*exp(-x).*sin(x)';
 fplot(f,[0 8],'b') title(f) xlabel('x') ylabel('y') grid on;  
 
     

I am a bit counfused with this fplot command ? becouse the the [0 8 ] means the the plot is betwen 0 to 8 how ever what is the size of axes x ? if I will use plot command then I have X and Y ,and X is a vector however in the flpot command my X is not a vector but an array ... how is this possible ?

Answer 1

[dpb]

clear x
f=@(x) 3*exp(-x).*sin(x);
fplot(f,[0 8],'b')

will produce the same plot -- fplot doesn't use your x array at all; it computes x internally and uses a number of points dependent upon the range given to provide (hopefully) a smooth plot. Try

hAx=gca;numel(hAx.Children.XData)

afterwards if you change the range or use the default range and see what you get...

Also NB: the string form for the functional is deprecated usage; use the alternate function handle instead.