// Convert float to rj string with 1234, _123, -123, _-12, 12.3, _1.2, or -1.2 format
char *ftostr4sign(const float& fx) {
const int x = fx * 10;
if (!WITHIN(x, -99, 999)) return itostr4sign((int)fx);
const bool neg = x < 0;
const int xx = neg ? -x : x;
conv[3] = neg ? '-' : (xx >= 100 ? DIGIMOD(xx, 100) : ' ');
conv[4] = DIGIMOD(xx, 10);
conv[5] = '.';
conv[6] = DIGIMOD(xx, 1);
return &conv[3];
}
// Convert float to rj string with _123, -123, _-12, or __-1 format
char *ftostr4sign(const float& x) { return itostr4sign((int)x); }