Simulink - skipping results equals to zero at writing to file

The results are shown in this picture http://img196.imageshack.us/img196/4943/2za.png

i want to skip results equals to 0 and dont write to file. File looks like at this picture for now. http://img203.imageshack.us/img203/4762/i2k9.png

my question is what to do if I need file with results dont equals 0, the exact time and the data, for example

Time Data
1     25
5    -50
6     52
30     5

I tried to use if case blocks with block which compare result to Zero but with no succes

Answer 1

[Zsolt]

I have found the solution, using the Enabled subsystem block with comparing to Zero all the results, and writing to file inside the subsystem block solves my problem. http://i.imgur.com/nDSVj9D.png http://img607.imageshack.us/img607/1739/1d93.png