Take a difference between the value and the lagged value dealing with NaN

Suppose I have a table T such as

            Running Dist      Swimming Dist
---------------------------------------------
Jan 18       100                 10
Feb 18       80                  NaN
Mar 18       105                 12

I want to take n-month changes of Running distance and Swimming distance. (But skips when there are NaN.)

In case of n=1, it will be

        Running Dist      Swimming Dist
  ---------------------------------------------

Feb 18       -20                  NaN
Mar 18       +25                 NaN

Please advise.

[Paolo]

What's the expected output for n = 2?

What about this table

             Running Dist      Swimming Dist
---------------------------------------------
Jan 18       100                 10
Feb 18       80                  NaN
Mar 18       105                 12
Apr 18       60                  NaN

?

Answer 1

[Sindhu Yerragunta]

Hi Alpedhuez,

One suggestion would be cleaning your data before you calculate the difference. The following link elaborates on how to clean and standardize the missing data.

https://www.mathworks.com/help/matlab/matlab_prog/clean-messy-and-missing-data-in-tables.html

Hope this information helps.

-Sindhu