sprintf deprecated

[objectobjectgroupgroup]

when compiling NumCalc i receive a warning that sprintf is deprecated

[f-brinkmann]

@schaastrommla can you comment on this? Is this something that should/could be changed?

[schaastrommla]

could be a problem with a specific compiler. currently it is just a warning, I guess it is because sprintf is c-style and not c++-style. I checked there are not many of these things in the code, I can replace them by c++ functions