random numbers in R

HHello

there is a matrix with 26 columns I have. The values in each row sum up to 1 it looks like

           [,1]       [,2]       [,3]       [,4]       [,5]       [,6]       [,7]      [,8]       [,9]      [,10]      [,11]
[1,] 0.02105263 0.01052632 0.01052632 0.04210526 0.01052632 0.06315789 0.03157895 0.1789474 0.07368421 0.07368421 0.02105263
[2,] 0.00000000 0.01176471 0.01176471 0.00000000 0.01176471 0.18823529 0.09411765 0.1764706 0.15294118 0.07058824 0.01176471
[3,] 0.00000000 0.00000000 0.02941176 0.01470588 0.04411765 0.11764706 0.05882353 0.2058824 0.07352941 0.08823529 0.00000000
          [,12]      [,13]      [,14] [,15]      [,16]      [,17]      [,18]      [,19]      [,20]      [,21]      [,22]
[1,] 0.04210526 0.04210526 0.05263158     0 0.03157895 0.02105263 0.00000000 0.04210526 0.01052632 0.05263158 0.02105263
[2,] 0.00000000 0.01176471 0.00000000     0 0.03529412 0.01176471 0.04705882 0.04705882 0.02352941 0.01176471 0.00000000
[3,] 0.02941176 0.02941176 0.02941176     0 0.05882353 0.01470588 0.02941176 0.02941176 0.02941176 0.01470588 0.00000000
          [,23]      [,24]      [,25]      [,26]
[1,] 0.06315789 0.03157895 0.03157895 0.02105263
[2,] 0.05882353 0.02352941 0.00000000 0.00000000
[3,] 0.02941176 0.01470588 0.00000000 0.05882353

now I would like to alterate the values to make up some new data. This would mean changing every value in a row randomly to a value in the range of - or plus 5 percent adn then still adding up to 1 with the rowsum. So in the column2 the 6 th value is currently 0 .18 and it should be (in the new data ) somewhere between 0.171 and 0.189 ( and and plus 5%). Alternatively, the value in the column should just be drawn from a normal distribution but should not differ too much from the original value. For large values like 0.18 maybe more als for values which are smaller. If the value is 0 it would be good to randimly decide whether it shoudl stay at 0 or increase by a range between 5% or 10% (taking as inital value something like 0.0001).is there an easy way tro do that?