Multi Row Tables / Combine information where row is equal?

Lets say I run simulations with different parameters A,B and for each of the A and B values i simulate another set of parameters x,y

Parset1=['A';'A';'B';'B'];
Parset2=['x';'y';'x';'y'];

And my simulation maybe produces numbers of false positives from the simulation:

FalsePositives=[3;5;6;9];
table(Parset1,Parset2,FalsePositives)

ans = 4×3 table
    Parset1    Parset2    FalsePositives
    _______    _______    ______________

       A          x             3       
       A          y             5       
       B          x             6       
       B          y             9       

And now maybe i want to get the total number of false positives for all simulations with same Parset1:

CumulativeFalsePositivesbyParset1=[8;8;15;15];
table(Parset1,Parset2,FalsePositives,CumulativeFalsePositivesbyParset1)

ans = 4×4 table
    Parset1    Parset2    FalsePositives    CumulativeFalsePositivesbyParset1
    _______    _______    ______________    _________________________________

       A          x             3                           8                
       A          y             5                           8                
       B          x             6                          15                
       B          y             9                          15                

Is there an easy way to do this with code??

Maybe even cleverer, can I make tables like below?

Parset1 | Parset2 | FalsePositives | CumulativeFalsePositives

-------------------------------------------------------------------------------------------------------

| x | 3 |

A --------------------------------------------------- 8

| y | 5 |

-------------------------------------------------------------------------------------------------------

| x | 6 |

B --------------------------------------------------- 15

| y | 9 |

-------------------------------------------------------------------------------------------------------

Answer 1

[Eric Sofen]

You can use varfun to apply the cumsum function to each group defined by Parset1.

Parset1=['A';'A';'B';'B'];
Parset2=['x';'y';'x';'y'];
FalsePositives=[3;5;6;9];
t = table(Parset1,Parset2,FalsePositives);

tc = varfun(@cumsum,t,"GroupingVariables","Parset1","InputVariables","FalsePositives")

% all in one table - copy over the original FalsePositives data
tc.FalsePositives = t.FalsePositives