Is the a matlab function that approximates the derivative of a function?

I am trying to find the equivalent function to 'derivative' function in Scilab, is there something similar in Matlab? I searched quite a lot,but no lack so far, any advice would be much appreciated!

Thank you!

Answer 1

[David Sanchez]

From Matlab documentation:

Y = diff(X)

calculates differences between adjacent elements of X.

Examples:

The quantity diff(y)./diff(x) is an approximate derivative.

x = [1 2 3 4 5];
y = diff(x)
y =
     1     1     1     1

z = diff(x,2)
z =
   0     0     0

Given,

A = rand(1,3,2,4);

diff(A) is the first-order difference along dimension 2.

diff(A,3,4) is the third-order difference along dimension 4.

[ana]

Thanks, but this is the approximations of derivative, but i need the function that approximates the derivative of a function, for example:

[fun,gun] = myfun(x)
fun = -1*LL(x)
gun = -1*'derivative'(LL,x)
end

in scilab you can use 'derivative' to approximate a function, but is there an equivalent to 'derivative' in matlab? As diff doesn't work Thanks!

[EDITED, Jan, code formatted]

[Jan]

@ana: What is "LL"?

@David: gradient uses a 2nd order method and is therefore more accurate than diff.

[dpb]

I'm assuming OP may be looking for symbolic derivative for his function rather than numeric approximation, maybe????