MATLAB: How to apply the following conditions

Question

hello, I have the following set of data in an array where I need to add the numbers on column 1 until the number on column 2 changes for example: column 2 has -1 for the first 28 figures so I add the numbers on column 1 and get 23 then add the numbers with a 1 then -1 and so on to get a list of the sums on every sign change.

     -0.000220000000000109                        -1
     -0.000129999999999963                        -1
      0.000150000000000095                        -1
     -0.000310000000000032                        -1
                   0.00305                        -1
     -0.000920000000000032                        -1
       0.00208000000000008                        -1
     -0.000480000000000036                        -1
     -8.99999999999235e-05                        -1
      0.000219999999999887                        -1
      0.000439999999999996                        -1
      0.000790000000000068                        -1
     -0.000350000000000072                        -1
     -0.000639999999999974                        -1
      -0.00143000000000004                        -1
       0.00127999999999995                        -1
      2.99999999999745e-05                        -1
     -0.000789999999999846                        -1
       0.00102999999999986                        -1
     -0.000399999999999956                        -1
      0.000870000000000148                        -1
     -0.000390000000000112                        -1
     -0.000219999999999887                        -1
     -0.000260000000000149                        -1
      -0.00109999999999988                        -1
       9.9999999999989e-05                        -1
      -0.00111000000000017                         1
                         0                         1
      0.000289999999999901                         1
     -0.000760000000000094                         1
      0.000430000000000152                         1
     -0.000770000000000159                         1
     -0.000139999999999807                         1
      0.000549999999999828                         1
      0.000400000000000178                         1
     -0.000420000000000087                         1
      0.000350000000000072                         1
       0.00042999999999993                         1
       0.00055000000000005                         1
      0.000580000000000025                         1
     -0.000609999999999999                         1
      -0.00012000000000012                         -1
     -0.000319999999999876                         -1
      0.000489999999999879                         -1
     -0.000350000000000072                         -1
      0.000240000000000018                         1
      0.000230000000000175                         1
       0.00132999999999983                         1

Answer 1

v = yourArray(:,2);
idx = cumsum([true;v(1:end-1)~= v(2:end)]);
totals = accumarray(idx, yourArray(:,1));