Question

I have a matrix like the following:

A =

 5     2    10    14    11

I am looking to create an additional row using this data. The element in the fifth column, second row, is constant and known: 100

By subtracting from the above row I am looking to insert these values

B =

63    65    75    89   100

E.g. 100-11 = 89. 89-14=75

To ultimately give the following:

[A;B]

ans =

 5     2    10    14    11
63    65    75    89   100

Any suggestions?

Answer 1

You can use the cumulative summation of the elements of A, via the MATLAB function cumsum, in order to perform this calculation:

knownvalue = 100; 
firstrow = [5     2    10    14    11]
secondrow = fliplr(knownvalue  - cumsum([0 firstrow(end:-1:2)]))