gradient with irregular grid

I have as a variable the temperature at a given depth and longitude, so it is a vector (317,1) where the 317 are all latitudes.

How do I get the gradient of this variable (which I call T) knowing that the latitude grid is irregular?

I can try

gradient_T=gradient(T,e1v) where e1v is the irregular vector?

Answer 1

[Star Strider]

The gradient function assumes a fixed step size for the second argument.

The way I calculate the numerical derivative using an irregular grid for the reference (assuming vectors here) is:

gradient_T = gradient(T) ./ gradient(e1v);

That will essentially calculate and generally produces the result I want.

.

Answer 2

[Nathan Hardenberg]

You can give the positions of the corresponding values as the second function argument. In your case the lattitude for each temperature measurement.

temperature = [30 29 28 27 26 25 24 23];
latitude = [1 2 3 4 5 10 11 20];

T = gradient(temperature, latitude)

T = 1×8

-1.0000 -1.0000 -1.0000 -1.0000 -0.3333 -0.3333 -0.2000 -0.1111