% function_plot.m
clear; clc

%% input data
N=input('Enter the number of points:               N = ');
% {
a=input('Enter the left endpoint of the interval:  a = ');
b=input('Enter the right endpoint of the interval: b = ');
%}
%ab=input('Enter the two endpoints of the interval: [a b] = '); a=min(ab); b=max(ab);

%%
fstr=input('Enter the function to be evaluated: f(t) = ','s');
pf=['@(t)' fstr];
pf=str2func(pf); % construct function handle from character vector

%% display
x=linspace(a,b,N)';
y=pf(x);

figure(1); clf
plot(x,y)
set(gca,'FontSize',14)
xlabel('x'); ylabel('y')
title(['Plotted function: f(t) = ' fstr],'FontWeight','normal')