foreach (-2.0,-1.9,-1.5,-1.1,-1.0,-0.9,-0.5,-0.1,-0)
{
 printf("string=%5s digits=%9f, float2big=%24.16e\n", $_, $_*0, $_*0);
} 

string=   -2 digits= 0.000000, float2big= 0.0000000000000000e+000
string= -1.9 digits= 0.000000, float2big= 0.0000000000000000e+000
string= -1.5 digits= 0.000000, float2big= 0.0000000000000000e+000
string= -1.1 digits= 0.000000, float2big= 0.0000000000000000e+000
string=   -1 digits= 0.000000, float2big= 0.0000000000000000e+000
string= -0.9 digits= 0.000000, float2big= 0.0000000000000000e+000
string= -0.5 digits= 0.000000, float2big= 0.0000000000000000e+000
string= -0.1 digits= 0.000000, float2big= 0.0000000000000000e+000
string=    0 digits= 0.000000, float2big= 0.0000000000000000e+000