Find the difference between two numbers in an array and create a new array

Hello, I am working on a meteoroogy project to calculate mean periods of buoyancy oscillation. Rather than do everything by hand, I figured it would be easier to throw them in matlab and have it calculate it. Right now, I'm at a point where I have calculated theta values in an array (11,1). For the equation I am using, I need to find the difference between theta values in order to use that number for my equation. (g/theta * differnece in Theta/difference in height)

All of these are in their own arrays. At this point, I need help figureing out what commands to use to have it figure out the difference between each of the theta values (and height, but I'm assuming I will end up just using the same code). I have attached the working code I have used to get each value so far.

One thing that can throw a wrench into my plans... there are two data sets that I have combined into one with a blank box in between them in order to split them apart. So I'll have to account for that, which will be a problem on its own. Thank you for your help!

Table = readtable('file.xlsx');

pres = Table(: , 1);

hght = Table(: , 2);

temp = Table(: , 3);

dwpt = Table(: , 4);

rh = Table(: , 5);

mixr = Table(: , 6);

Rdcpdry = .286;

thing = Rdcpdry;

tp1 = (1000 ./ pres{: , 1}) .^thing;

theta = (temp{: , 1}) .* tp1;

Answer 1

[Sargondjani]

d_theta=diff(theta);

[Ian Mason]

That was great! Thank you! Now I am running into issues calculing the d_hght. I'm trying to use the code d_hght = diff(hght);

But, I'm getting this error... Check for missing argument or incorrect argument data type in call to function 'diff'.

[Ian Mason]

Figured it out. I forgot to put the call to the table in brackets.