what is inline(vectorize function), also why to use fliplr for this?

clc
clear all
close all
syms x
f = input('Enter the function')
fL = input('Enter the interval on which the function is defined')
yr = input('Enter the axis of rotation')
iL = input('integration limits')
volume = pi*int((f-yr)^2,iL(1),iL(2));
disp(['Volume is: ',num2str(double(volume))])
fx = inline(vectorize(f));
xvals = linspace(fL(1),fL(2),201);
xvals = fliplr(xvals);
xivals = linspace(iL(1),iL(2),201);
xivalsr = fliplr(xivals);
xlim = [fL(1) fL(2)+0.5];
ylim = fx(xlim);
figure('Position',[100 200 560 420])
subplot(2,1,1)
hold on
plot(xvals,fx(xvals),'-b','LineWidth',2);
[X,Y,Z] = cylinder(fx(xivals)-yr,100);
figure('Position',[700 200 560 420])
Z = iL(1) + Z.*(iL(2)-iL(1));
surf(Z,Y+yr,X,'EdgeColor','none','FaceColor','flat','FaceAlpha',0.6);
hold on
plot([iL(1),iL(2)],[yr yr], 'r-', 'LineWidth', 2);
xlabel('X-axis');
ylabel('Y-axis');
zlabel('Z-axis');
view(22,11)

Answer 1

[Chandler Hall]

Vectorize just adds some '.' to a string so that it might be used as a vectorized function, i.e.,

>> vectorize('(x^3)/y')

ans =

'(x.^3)./y'

Why use fliplr? That's impossible to say because it actually has no effect at all. xvals is only used in the subsequent plot, which produces the same output if the vectors are in ascending order vs descending, and xivalsr is unused.

[Dhairya]

thanks a lot sir

[Walter Roberson]

Changing the order using fliplr() could potentially lead to a difference as to exactly where the "seam" is in the plot of the cylinder.

Answer 2

[Steven Lord]

Do not use inline. Its use has been discouraged for probably around 15 years now.

To convert a piece of text data to something that you can call as a function use str2func.

To convert a symbolic expression to something that you can call as a function use matlabFunction.

[Dhairya]

sir we have an exam tomorrow and this the only way we are taught

if possible could you please give some description about it?

[Steven Lord]

See the documentation for str2func and matlabFunction for examples of how to use each function.