Scaling the derivative of a data vector?

I have a vector of data, and I would like to scale the derivative of this data by some amount, and see the how it changes the original data.

How can I do this? Thanks.

Answer 1

[Jan]

You could calculate the gradient, multiply if by the factor and integrate.

But the result can be found without calculating the gradient explicitely also. Hint: Write down the (forward or backward or centered) difference quotient.

Is this a homework?

[Superfish]

Not homework. Just a guy whose brain is failing at maths trying to do some simple data analysis :)

Thanks, upon researching numerical integration more just now I found the function cumtrapz, I was using trapz and getting confused.

[Jan]

Another hint: x = rand(1, 6);

disp(gradient(x)); disp(gradient(x)*2); disp(gradient(x*2));

See: http://en.wikipedia.org/wiki/Linear_Operator