Its always better to use a 'double' array instead of float. If you are very specific about float array, you can initialize it by explicitly type-casting each element as shown below. const float feature_scal_intervall_low[ NR_FEATURES ] = { (float)0.1,(float)0.0,(float)0.1,(float)0.1,(float)0.3 ,(float)0.2,(float)0.1,(float)0.1,(float)0.0,(float)0.2 }; "A robust program is resistant to errors -- it either works correctly, or it does not work at all; whereas a fault tolerant program must actually recover from errors."