Replacing row specific value rows of table with corresponding table values

I need to replace all the values of 999999 in a row of a table with the value 0.0001, then i need to go to the next row and replace the same values of 999999 with 0.0002, i need to do this for variable numbers of rows depending on the data being read in.

the code i have working so far is as follows:

i=i+1;

    for
    x=1:Number_of_Compounds;

    Number_of_Compounds(i,:)=(Number_of_Compounds==999999)=MDL_Codes(i)

    i=i+1

end

In Short i need to be able to replace identifier numbers in a table with another value unique to that row.

I also tried using the find command but was unable to figure out how to indicie it so that it only made changes to one row and not the entire spreadsheet.

for x=1:Number_of_Compounds;

TableCompounds(i)=Table_Compounds(find(Table_Compounds==999999))=MDL_Codes(i)

i=i+1;

Answer 1

[KSSV]

N = 10 ;
A = rand(N) ;
% put NaN's randomly 

A(randperm(N*N,round(40*N*N/100))) = NaN ;
B = A ;
% replace NaN's
for i = 1:N
    num = i/1000 ;  % replace with this 
    A(isnan(A(i,:)),:) = num ;
end

[Matt Brianik]

The isn't working in the way that I need it to. issue is that I need to replace different values within each row, NAN values in row 1 need to be x, NAN values in row 2 need to be y, etc... this doesn't do that