typename std::enable_if<std::is_floating_point<T>::value, bool>::type toType(T& r, const char* p)
{
// Skip leading white space, if any.
while (white_space(*p))
{
p += 1;
}
r = 0.0;
int c = 0; // counter to check how many numbers we got!
// Get the sign!
bool neg = false;
if (*p == '-')
{
neg = true;
++p;
}
else if (*p == '+')
{
neg = false;
++p;
}
// Get the digits before decimal point
while (valid_digit(*p))
{
r = (r * 10.0) + (*p - '0');
++p;
++c;
}
// Get the digits after decimal point
if (*p == '.')
{
T f = 0.0;
T scale = 1.0;
++p;
while (*p >= '0' && *p <= '9')
{
f = (f * 10.0) + (*p - '0');
++p;
scale *= 10.0;
++c;
}
r += f / scale;
}
// FIRST CHECK:
if (c == 0)
{
return false;
} // we got no dezimal places: invalid number!
// Get the digits after the "e"/"E" (exponenet)
if (*p == 'e' || *p == 'E')
{
unsigned int e = 0;
bool negE = false;
++p;
if (*p == '-')
{
negE = true;
++p;
}
else if (*p == '+')
{
negE = false;
++p;
}
// Get exponent
c = 0;
while (valid_digit(*p))
{
e = (e * 10) + (*p - '0');
++p;
++c;
}
// Check exponent limits!
// if( !neg && e>std::numeric_limits<T>::max_exponent10 ){
// e = std::numeric_limits<T>::max_exponent10;
// }else if(e < std::numeric_limits<T>::min_exponent10 ){
// e = std::numeric_limits<T>::max_exponent10;
// }
// SECOND CHECK:
if (c == 0)
{
return false;
} // we got no exponent: invalid number!
T scaleE = 1.0;
// Calculate scaling factor.
while (e >= 50)
{
scaleE *= 1E50;
e -= 50;
}
// while (e >= 8) { scaleE *= 1E8; e -= 8; }
while (e > 0)
{
scaleE *= 10.0;
e -= 1;
}
if (negE)
{
r /= scaleE;
}
else
{
r *= scaleE;
}
}
// POST CHECK:
// skip post whitespaces
while (white_space(*p))
{
++p;
}
if (*p != '\0')
{
return false;
} // if next character is not the terminating character: invalid number!
// Apply sign to number
if (neg)
{
r = -r;
}
return true;
}
static float _atof(const char *p)
{
int frac = 0;
float sign, value, scale;
// Skip leading white space, if any.
while (white_space(*p) ) {
p += 1;
}
// Get sign, if any.
sign = 1.0f;
if (*p == '-') {
sign = -1.0f;
p += 1;
} else if (*p == '+') {
p += 1;
}
// Get digits before decimal point or exponent, if any.
value = 0.0f;
while (valid_digit(*p)) {
value = value * 10.0f + (*p - '0');
p += 1;
}
// Get digits after decimal point, if any.
if (*p == '.') {
float pow10 = 10.0f;
p += 1;
while (valid_digit(*p)) {
value += (*p - '0') / pow10;
pow10 *= 10.0f;
p += 1;
}
}
// Handle exponent, if any.
scale = 1.0f;
if ((*p == 'e') || (*p == 'E')) {
unsigned int expon;
p += 1;
// Get sign of exponent, if any.
frac = 0;
if (*p == '-') {
frac = 1;
p += 1;
} else if (*p == '+') {
p += 1;
}
// Get digits of exponent, if any.
expon = 0;
while (valid_digit(*p)) {
expon = expon * 10 + (*p - '0');
p += 1;
}
if (expon > 308)
expon = 308;
// Calculate scaling factor.
// while (expon >= 50) { scale *= 1E50f; expon -= 50; }
while (expon >= 8) { scale *= 1E8f; expon -= 8; }
while (expon > 0) { scale *= 10.0f; expon -= 1; }
}
// Return signed and scaled floating point result.
return sign * (frac ? (value / scale) : (value * scale));
}
T CharToNum::atof2(const char *num)
{
//Improvement of the atof() function
//Original source from http://tinodidriksen.com/2011/05/28/cpp-convert-string-to-double-speed/
// Tino Didriksen, 2014
// Skip leading white space, if any.
while (white_space(*num))
{
num += 1;
}
T r = 0.0;
unsigned int c = 0; // counter to check how many numbers we got!
// Get the sign!
bool neg = false;
if (*num == '-')
{
neg = true;
++num;
}
else if (*num == '+'){
neg = false;
++num;
}
// Get the digits before decimal point
while (valid_digit(*num))
{
r = (r * 10.0) + (*num - '0');
++num;
++c;
}
// Get the digits after decimal point
if (*num == '.') {
T f = 0.0;
T scale = 1.0;
++num;
while (*num >= '0' && *num <= '9')
{
f = (f*10.0) + (*num - '0');
++num;
scale *= 10.0;
++c;
}
r += f / scale;
}
// FIRST CHECK:
if (c == 0)
{
// We got no dezimal places! this cannot be any number!
throw ("BadDataException: the strinh has no dezimal place.", "Conversion to number aborted.");
}
// Get the digits after the "e"/"E" (exponenet)
if (*num == 'e' || *num == 'E'){
unsigned int e = 0;
bool negE = false;
++num;
if (*num == '-')
{
negE = true;
++num;
}
else if (*num == '+')
{
negE = false;
++num;
}
// Get exponent
c = 0;
while (valid_digit(*num))
{
e = (e * 10) + (*num - '0');
++num; ++c;
}
if (!neg && e > std::numeric_limits<T>::max_exponent10)
{
e = std::numeric_limits<T>::max_exponent10;
}
else if (e < std::numeric_limits<T>::min_exponent10)
{
e = std::numeric_limits<T>::max_exponent10;
}
// SECOND CHECK:
if (c == 0)
{
// We got no exponent! this was not intended!!
throw ("BadDataException: the string has no exponent.", "Conversion to number aborted.");
}
T scaleE = 1.0;
// Calculate scaling factor.
while (e >= 50)
{
scaleE *= 1E50;
e -= 50;
}
while (e > 0)
{
scaleE *= 10.0;
e -= 1;
}
if (negE)
{
r /= scaleE;
}
else
{
r *= scaleE;
}
}
// POST CHECK:
// skip post whitespaces
while (white_space(*num))
{
++num;
}
if (*num != '\0')
{
// If next character is not the terminating character
throw ("BadDataException: the next character is not \n.", "Conversion to number aborted.");
}
// Apply sign to number
if (neg)
{
r = -r;
}
return r;
}