MATLAB: How to calculate a derivative

derivative and integration

can some one guide me how to calculate a derivative and integration in matlab . can you please give a little example.

Best Answer

Symbolically
syms x real
f = 1/x
int(f,1,2)  % integration
ans =
log(2)
diff(f)  %differentiation
ans =
 -1/x^2
[edit - amplification]
syms x a b real positive
f = 1/x
f =
1/x
int(f) % without limits
ans =
log(x)
int(f,a,b) % with limits
ans =
log(b) - log(a)
fn  = matlabFunction(f) % convert symbolic to anonymous function
fn = 
      @(x)1./x
quadgk(fn,1,2) % integrate numerically
ans =
      0.6931
log(2)  % previous result from symbolic integration
ans =
      0.6931
   (fn(2+1e-6)-fn(2))/1e-6  %numerical derivative at fn(2)
ans =
     -0.2500
   subs(diff(f),2) %substitute 2 into symbolic result previously obtained
ans =
     -0.2500
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