Forward, backward and central differences

trying to calculate the forward, backward and central difference for tanx+cosy with a step of 0.1 and x and y domains between 1 and 5.

[madhan ravi]

What have you tried so far?

[Image Analyst]

What is your definition of those 3 differences?

[HoboHarry]

i'm not even sure where to start. i know for just calculating one for tanx by itself uses (f(x+h)-f(x))/h; for fwd difference where h is the step. but not sure where to go with two variables

Answer 1

[Image Analyst]

Try conv():

kernel = [1, -1];
output = conv(signal, kernel);
kernel = [-1, 1];
output = conv(signal, kernel);
kernel = [1, -2, 1];
output = conv(signal, kernel);

See if that gives you what you want. Do you have a signal and the desired output so we can check it?