Just declare your variable as a float and myfile.print them to SD.
I was so used of converting everything to String that i didn't thought it
So thanks!!
In the otherhand the other two answers didn't not help because:
myFile = SD.open(filename, FILE_WRITE);
myFile.print(test1);
myFile.print(",");
myFile.print(test2);
myFile.print(",");
i don't want to write something different i want to give different filename!
For the date i have to find a way to change it automatically...
Thanks in advance!