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add GeographicLib

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This commit is contained in:
Sven Czarnian
2021-11-22 16:16:36 +01:00
parent b1b6b5c790
commit 09e29afe7b
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external/include/GeographicLib/Utility.hpp vendored Normal file
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/**
* \file Utility.hpp
* \brief Header for GeographicLib::Utility class
*
* Copyright (c) Charles Karney (2011-2020) <charles@karney.com> and licensed
* under the MIT/X11 License. For more information, see
* https://geographiclib.sourceforge.io/
**********************************************************************/
#if !defined(GEOGRAPHICLIB_UTILITY_HPP)
#define GEOGRAPHICLIB_UTILITY_HPP 1
#include <GeographicLib/Constants.hpp>
#include <iomanip>
#include <vector>
#include <sstream>
#include <cctype>
#include <ctime>
#include <cstring>
#if defined(_MSC_VER)
// Squelch warnings about constant conditional expressions and unsafe gmtime
# pragma warning (push)
# pragma warning (disable: 4127 4996)
#endif
namespace GeographicLib {
/**
* \brief Some utility routines for %GeographicLib
*
* Example of use:
* \include example-Utility.cpp
**********************************************************************/
class GEOGRAPHICLIB_EXPORT Utility {
private:
static bool gregorian(int y, int m, int d) {
// The original cut over to the Gregorian calendar in Pope Gregory XIII's
// time had 1582-10-04 followed by 1582-10-15. Here we implement the
// switch over used by the English-speaking world where 1752-09-02 was
// followed by 1752-09-14. We also assume that the year always begins
// with January 1, whereas in reality it often was reckoned to begin in
// March.
return 100 * (100 * y + m) + d >= 17520914; // or 15821015
}
static bool gregorian(int s) {
return s >= 639799; // 1752-09-14
}
public:
/**
* Convert a date to the day numbering sequentially starting with
* 0001-01-01 as day 1.
*
* @param[in] y the year (must be positive).
* @param[in] m the month, Jan = 1, etc. (must be positive). Default = 1.
* @param[in] d the day of the month (must be positive). Default = 1.
* @return the sequential day number.
**********************************************************************/
static int day(int y, int m = 1, int d = 1) {
// Convert from date to sequential day and vice versa
//
// Here is some code to convert a date to sequential day and vice
// versa. The sequential day is numbered so that January 1, 1 AD is day 1
// (a Saturday). So this is offset from the "Julian" day which starts the
// numbering with 4713 BC.
//
// This is inspired by a talk by John Conway at the John von Neumann
// National Supercomputer Center when he described his Doomsday algorithm
// for figuring the day of the week. The code avoids explicitly doing ifs
// (except for the decision of whether to use the Julian or Gregorian
// calendar). Instead the equivalent result is achieved using integer
// arithmetic. I got this idea from the routine for the day of the week
// in MACLisp (I believe that that routine was written by Guy Steele).
//
// There are three issues to take care of
//
// 1. the rules for leap years,
// 2. the inconvenient placement of leap days at the end of February,
// 3. the irregular pattern of month lengths.
//
// We deal with these as follows:
//
// 1. Leap years are given by simple rules which are straightforward to
// accommodate.
//
// 2. We simplify the calculations by moving January and February to the
// previous year. Here we internally number the months March–December,
// January, February as 0–9, 10, 11.
//
// 3. The pattern of month lengths from March through January is regular
// with a 5-month period—31, 30, 31, 30, 31, 31, 30, 31, 30, 31, 31. The
// 5-month period is 153 days long. Since February is now at the end of
// the year, we don't need to include its length in this part of the
// calculation.
bool greg = gregorian(y, m, d);
y += (m + 9) / 12 - 1; // Move Jan and Feb to previous year,
m = (m + 9) % 12; // making March month 0.
return
(1461 * y) / 4 // Julian years converted to days. Julian year is 365 +
// 1/4 = 1461/4 days.
// Gregorian leap year corrections. The 2 offset with respect to the
// Julian calendar synchronizes the vernal equinox with that at the
// time of the Council of Nicea (325 AD).
+ (greg ? (y / 100) / 4 - (y / 100) + 2 : 0)
+ (153 * m + 2) / 5 // The zero-based start of the m'th month
+ d - 1 // The zero-based day
- 305; // The number of days between March 1 and December 31.
// This makes 0001-01-01 day 1
}
/**
* Convert a date to the day numbering sequentially starting with
* 0001-01-01 as day 1.
*
* @param[in] y the year (must be positive).
* @param[in] m the month, Jan = 1, etc. (must be positive). Default = 1.
* @param[in] d the day of the month (must be positive). Default = 1.
* @param[in] check whether to check the date.
* @exception GeographicErr if the date is invalid and \e check is true.
* @return the sequential day number.
**********************************************************************/
static int day(int y, int m, int d, bool check) {
int s = day(y, m, d);
if (!check)
return s;
int y1, m1, d1;
date(s, y1, m1, d1);
if (!(s > 0 && y == y1 && m == m1 && d == d1))
throw GeographicErr("Invalid date " +
str(y) + "-" + str(m) + "-" + str(d)
+ (s > 0 ? "; use " +
str(y1) + "-" + str(m1) + "-" + str(d1) :
" before 0001-01-01"));
return s;
}
/**
* Given a day (counting from 0001-01-01 as day 1), return the date.
*
* @param[in] s the sequential day number (must be positive)
* @param[out] y the year.
* @param[out] m the month, Jan = 1, etc.
* @param[out] d the day of the month.
**********************************************************************/
static void date(int s, int& y, int& m, int& d) {
int c = 0;
bool greg = gregorian(s);
s += 305; // s = 0 on March 1, 1BC
if (greg) {
s -= 2; // The 2 day Gregorian offset
// Determine century with the Gregorian rules for leap years. The
// Gregorian year is 365 + 1/4 - 1/100 + 1/400 = 146097/400 days.
c = (4 * s + 3) / 146097;
s -= (c * 146097) / 4; // s = 0 at beginning of century
}
y = (4 * s + 3) / 1461; // Determine the year using Julian rules.
s -= (1461 * y) / 4; // s = 0 at start of year, i.e., March 1
y += c * 100; // Assemble full year
m = (5 * s + 2) / 153; // Determine the month
s -= (153 * m + 2) / 5; // s = 0 at beginning of month
d = s + 1; // Determine day of month
y += (m + 2) / 12; // Move Jan and Feb back to original year
m = (m + 2) % 12 + 1; // Renumber the months so January = 1
}
/**
* Given a date as a string in the format yyyy, yyyy-mm, or yyyy-mm-dd,
* return the numeric values for the year, month, and day. No checking is
* done on these values. The string "now" is interpreted as the present
* date (in UTC).
*
* @param[in] s the date in string format.
* @param[out] y the year.
* @param[out] m the month, Jan = 1, etc.
* @param[out] d the day of the month.
* @exception GeographicErr is \e s is malformed.
**********************************************************************/
static void date(const std::string& s, int& y, int& m, int& d) {
if (s == "now") {
std::time_t t = std::time(0);
struct tm* now = gmtime(&t);
y = now->tm_year + 1900;
m = now->tm_mon + 1;
d = now->tm_mday;
return;
}
int y1, m1 = 1, d1 = 1;
const char* digits = "0123456789";
std::string::size_type p1 = s.find_first_not_of(digits);
if (p1 == std::string::npos)
y1 = val<int>(s);
else if (s[p1] != '-')
throw GeographicErr("Delimiter not hyphen in date " + s);
else if (p1 == 0)
throw GeographicErr("Empty year field in date " + s);
else {
y1 = val<int>(s.substr(0, p1));
if (++p1 == s.size())
throw GeographicErr("Empty month field in date " + s);
std::string::size_type p2 = s.find_first_not_of(digits, p1);
if (p2 == std::string::npos)
m1 = val<int>(s.substr(p1));
else if (s[p2] != '-')
throw GeographicErr("Delimiter not hyphen in date " + s);
else if (p2 == p1)
throw GeographicErr("Empty month field in date " + s);
else {
m1 = val<int>(s.substr(p1, p2 - p1));
if (++p2 == s.size())
throw GeographicErr("Empty day field in date " + s);
d1 = val<int>(s.substr(p2));
}
}
y = y1; m = m1; d = d1;
}
/**
* Given the date, return the day of the week.
*
* @param[in] y the year (must be positive).
* @param[in] m the month, Jan = 1, etc. (must be positive).
* @param[in] d the day of the month (must be positive).
* @return the day of the week with Sunday, Monday--Saturday = 0,
* 1--6.
**********************************************************************/
static int dow(int y, int m, int d) { return dow(day(y, m, d)); }
/**
* Given the sequential day, return the day of the week.
*
* @param[in] s the sequential day (must be positive).
* @return the day of the week with Sunday, Monday--Saturday = 0,
* 1--6.
**********************************************************************/
static int dow(int s) {
return (s + 5) % 7; // The 5 offset makes day 1 (0001-01-01) a Saturday.
}
/**
* Convert a string representing a date to a fractional year.
*
* @tparam T the type of the argument.
* @param[in] s the string to be converted.
* @exception GeographicErr if \e s can't be interpreted as a date.
* @return the fractional year.
*
* The string is first read as an ordinary number (e.g., 2010 or 2012.5);
* if this is successful, the value is returned. Otherwise the string
* should be of the form yyyy-mm or yyyy-mm-dd and this is converted to a
* number with 2010-01-01 giving 2010.0 and 2012-07-03 giving 2012.5.
**********************************************************************/
template<typename T> static T fractionalyear(const std::string& s) {
try {
return val<T>(s);
}
catch (const std::exception&) {}
int y, m, d;
date(s, y, m, d);
int t = day(y, m, d, true);
return T(y) + T(t - day(y)) / T(day(y + 1) - day(y));
}
/**
* Convert a object of type T to a string.
*
* @tparam T the type of the argument.
* @param[in] x the value to be converted.
* @param[in] p the precision used (default &minus;1).
* @exception std::bad_alloc if memory for the string can't be allocated.
* @return the string representation.
*
* If \e p &ge; 0, then the number fixed format is used with p bits of
* precision. With p < 0, there is no manipulation of the format.
**********************************************************************/
template<typename T> static std::string str(T x, int p = -1) {
std::ostringstream s;
if (p >= 0) s << std::fixed << std::setprecision(p);
s << x; return s.str();
}
/**
* Convert a Math::real object to a string.
*
* @param[in] x the value to be converted.
* @param[in] p the precision used (default &minus;1).
* @exception std::bad_alloc if memory for the string can't be allocated.
* @return the string representation.
*
* If \e p &ge; 0, then the number fixed format is used with p bits of
* precision. With p < 0, there is no manipulation of the format. This is
* an overload of str<T> which deals with inf and nan.
**********************************************************************/
static std::string str(Math::real x, int p = -1) {
using std::isfinite;
if (!isfinite(x))
return x < 0 ? std::string("-inf") :
(x > 0 ? std::string("inf") : std::string("nan"));
std::ostringstream s;
#if GEOGRAPHICLIB_PRECISION == 4
// boost-quadmath treats precision == 0 as "use as many digits as
// necessary" (see https://svn.boost.org/trac/boost/ticket/10103), so...
using std::floor; using std::fmod;
if (p == 0) {
x += Math::real(0.5);
Math::real ix = floor(x);
// Implement the "round ties to even" rule
x = (ix == x && fmod(ix, Math::real(2)) == 1) ? ix - 1 : ix;
s << std::fixed << std::setprecision(1) << x;
std::string r(s.str());
// strip off trailing ".0"
return r.substr(0, (std::max)(int(r.size()) - 2, 0));
}
#endif
if (p >= 0) s << std::fixed << std::setprecision(p);
s << x; return s.str();
}
/**
* Trim the white space from the beginning and end of a string.
*
* @param[in] s the string to be trimmed
* @return the trimmed string
**********************************************************************/
static std::string trim(const std::string& s) {
unsigned
beg = 0,
end = unsigned(s.size());
while (beg < end && isspace(s[beg]))
++beg;
while (beg < end && isspace(s[end - 1]))
--end;
return std::string(s, beg, end-beg);
}
/**
* Convert a string to type T.
*
* @tparam T the type of the return value.
* @param[in] s the string to be converted.
* @exception GeographicErr is \e s is not readable as a T.
* @return object of type T.
*
* White space at the beginning and end of \e s is ignored.
*
* Special handling is provided for some types.
*
* If T is a floating point type, then inf and nan are recognized.
*
* If T is bool, then \e s should either be string a representing 0 (false)
* or 1 (true) or one of the strings
* - "false", "f", "nil", "no", "n", "off", or "" meaning false,
* - "true", "t", "yes", "y", or "on" meaning true;
* .
* case is ignored.
*
* If T is std::string, then \e s is returned (with the white space at the
* beginning and end removed).
**********************************************************************/
template<typename T> static T val(const std::string& s) {
// If T is bool, then the specialization val<bool>() defined below is
// used.
T x;
std::string errmsg, t(trim(s));
do { // Executed once (provides the ability to break)
std::istringstream is(t);
if (!(is >> x)) {
errmsg = "Cannot decode " + t;
break;
}
int pos = int(is.tellg()); // Returns -1 at end of string?
if (!(pos < 0 || pos == int(t.size()))) {
errmsg = "Extra text " + t.substr(pos) + " at end of " + t;
break;
}
return x;
} while (false);
x = std::numeric_limits<T>::is_integer ? 0 : nummatch<T>(t);
if (x == 0)
throw GeographicErr(errmsg);
return x;
}
/**
* \deprecated An old name for val<T>(s).
**********************************************************************/
template<typename T>
GEOGRAPHICLIB_DEPRECATED("Use Utility::val<T>(s)")
static T num(const std::string& s) {
return val<T>(s);
}
/**
* Match "nan" and "inf" (and variants thereof) in a string.
*
* @tparam T the type of the return value (this should be a floating point
* type).
* @param[in] s the string to be matched.
* @return appropriate special value (&plusmn;&infin;, nan) or 0 if none is
* found.
*
* White space is not allowed at the beginning or end of \e s.
**********************************************************************/
template<typename T> static T nummatch(const std::string& s) {
if (s.length() < 3)
return 0;
std::string t(s);
for (std::string::iterator p = t.begin(); p != t.end(); ++p)
*p = char(std::toupper(*p));
for (size_t i = s.length(); i--;)
t[i] = char(std::toupper(s[i]));
int sign = t[0] == '-' ? -1 : 1;
std::string::size_type p0 = t[0] == '-' || t[0] == '+' ? 1 : 0;
std::string::size_type p1 = t.find_last_not_of('0');
if (p1 == std::string::npos || p1 + 1 < p0 + 3)
return 0;
// Strip off sign and trailing 0s
t = t.substr(p0, p1 + 1 - p0); // Length at least 3
if (t == "NAN" || t == "1.#QNAN" || t == "1.#SNAN" || t == "1.#IND" ||
t == "1.#R")
return Math::NaN<T>();
else if (t == "INF" || t == "1.#INF")
return sign * Math::infinity<T>();
return 0;
}
/**
* Read a simple fraction, e.g., 3/4, from a string to an object of type T.
*
* @tparam T the type of the return value.
* @param[in] s the string to be converted.
* @exception GeographicErr is \e s is not readable as a fraction of type
* T.
* @return object of type T
*
* \note The msys shell under Windows converts arguments which look like
* pathnames into their Windows equivalents. As a result the argument
* "-1/300" gets mangled into something unrecognizable. A workaround is to
* use a floating point number in the numerator, i.e., "-1.0/300". (Recent
* versions of the msys shell appear \e not to have this problem.)
**********************************************************************/
template<typename T> static T fract(const std::string& s) {
std::string::size_type delim = s.find('/');
return
!(delim != std::string::npos && delim >= 1 && delim + 2 <= s.size()) ?
val<T>(s) :
// delim in [1, size() - 2]
val<T>(s.substr(0, delim)) / val<T>(s.substr(delim + 1));
}
/**
* Lookup up a character in a string.
*
* @param[in] s the string to be searched.
* @param[in] c the character to look for.
* @return the index of the first occurrence character in the string or
* &minus;1 is the character is not present.
*
* \e c is converted to upper case before search \e s. Therefore, it is
* intended that \e s should not contain any lower case letters.
**********************************************************************/
static int lookup(const std::string& s, char c) {
std::string::size_type r = s.find(char(std::toupper(c)));
return r == std::string::npos ? -1 : int(r);
}
/**
* Lookup up a character in a char*.
*
* @param[in] s the char* string to be searched.
* @param[in] c the character to look for.
* @return the index of the first occurrence character in the string or
* &minus;1 is the character is not present.
*
* \e c is converted to upper case before search \e s. Therefore, it is
* intended that \e s should not contain any lower case letters.
**********************************************************************/
static int lookup(const char* s, char c) {
const char* p = std::strchr(s, std::toupper(c));
return p != NULL ? int(p - s) : -1;
}
/**
* Read data of type ExtT from a binary stream to an array of type IntT.
* The data in the file is in (bigendp ? big : little)-endian format.
*
* @tparam ExtT the type of the objects in the binary stream (external).
* @tparam IntT the type of the objects in the array (internal).
* @tparam bigendp true if the external storage format is big-endian.
* @param[in] str the input stream containing the data of type ExtT
* (external).
* @param[out] array the output array of type IntT (internal).
* @param[in] num the size of the array.
* @exception GeographicErr if the data cannot be read.
**********************************************************************/
template<typename ExtT, typename IntT, bool bigendp>
static void readarray(std::istream& str, IntT array[], size_t num) {
#if GEOGRAPHICLIB_PRECISION < 4
if (sizeof(IntT) == sizeof(ExtT) &&
std::numeric_limits<IntT>::is_integer ==
std::numeric_limits<ExtT>::is_integer)
{
// Data is compatible (aside from the issue of endian-ness).
str.read(reinterpret_cast<char*>(array), num * sizeof(ExtT));
if (!str.good())
throw GeographicErr("Failure reading data");
if (bigendp != Math::bigendian) { // endian mismatch -> swap bytes
for (size_t i = num; i--;)
array[i] = Math::swab<IntT>(array[i]);
}
}
else
#endif
{
const int bufsize = 1024; // read this many values at a time
ExtT buffer[bufsize]; // temporary buffer
int k = int(num); // data values left to read
int i = 0; // index into output array
while (k) {
int n = (std::min)(k, bufsize);
str.read(reinterpret_cast<char*>(buffer), n * sizeof(ExtT));
if (!str.good())
throw GeographicErr("Failure reading data");
for (int j = 0; j < n; ++j)
// fix endian-ness and cast to IntT
array[i++] = IntT(bigendp == Math::bigendian ? buffer[j] :
Math::swab<ExtT>(buffer[j]));
k -= n;
}
}
return;
}
/**
* Read data of type ExtT from a binary stream to a vector array of type
* IntT. The data in the file is in (bigendp ? big : little)-endian
* format.
*
* @tparam ExtT the type of the objects in the binary stream (external).
* @tparam IntT the type of the objects in the array (internal).
* @tparam bigendp true if the external storage format is big-endian.
* @param[in] str the input stream containing the data of type ExtT
* (external).
* @param[out] array the output vector of type IntT (internal).
* @exception GeographicErr if the data cannot be read.
**********************************************************************/
template<typename ExtT, typename IntT, bool bigendp>
static void readarray(std::istream& str, std::vector<IntT>& array) {
if (array.size() > 0)
readarray<ExtT, IntT, bigendp>(str, &array[0], array.size());
}
/**
* Write data in an array of type IntT as type ExtT to a binary stream.
* The data in the file is in (bigendp ? big : little)-endian format.
*
* @tparam ExtT the type of the objects in the binary stream (external).
* @tparam IntT the type of the objects in the array (internal).
* @tparam bigendp true if the external storage format is big-endian.
* @param[out] str the output stream for the data of type ExtT (external).
* @param[in] array the input array of type IntT (internal).
* @param[in] num the size of the array.
* @exception GeographicErr if the data cannot be written.
**********************************************************************/
template<typename ExtT, typename IntT, bool bigendp>
static void writearray(std::ostream& str, const IntT array[], size_t num)
{
#if GEOGRAPHICLIB_PRECISION < 4
if (sizeof(IntT) == sizeof(ExtT) &&
std::numeric_limits<IntT>::is_integer ==
std::numeric_limits<ExtT>::is_integer &&
bigendp == Math::bigendian)
{
// Data is compatible (including endian-ness).
str.write(reinterpret_cast<const char*>(array), num * sizeof(ExtT));
if (!str.good())
throw GeographicErr("Failure writing data");
}
else
#endif
{
const int bufsize = 1024; // write this many values at a time
ExtT buffer[bufsize]; // temporary buffer
int k = int(num); // data values left to write
int i = 0; // index into output array
while (k) {
int n = (std::min)(k, bufsize);
for (int j = 0; j < n; ++j)
// cast to ExtT and fix endian-ness
buffer[j] = bigendp == Math::bigendian ? ExtT(array[i++]) :
Math::swab<ExtT>(ExtT(array[i++]));
str.write(reinterpret_cast<const char*>(buffer), n * sizeof(ExtT));
if (!str.good())
throw GeographicErr("Failure writing data");
k -= n;
}
}
return;
}
/**
* Write data in an array of type IntT as type ExtT to a binary stream.
* The data in the file is in (bigendp ? big : little)-endian format.
*
* @tparam ExtT the type of the objects in the binary stream (external).
* @tparam IntT the type of the objects in the array (internal).
* @tparam bigendp true if the external storage format is big-endian.
* @param[out] str the output stream for the data of type ExtT (external).
* @param[in] array the input vector of type IntT (internal).
* @exception GeographicErr if the data cannot be written.
**********************************************************************/
template<typename ExtT, typename IntT, bool bigendp>
static void writearray(std::ostream& str, std::vector<IntT>& array) {
if (array.size() > 0)
writearray<ExtT, IntT, bigendp>(str, &array[0], array.size());
}
/**
* Parse a KEY [=] VALUE line.
*
* @param[in] line the input line.
* @param[out] key the KEY.
* @param[out] value the VALUE.
* @param[in] delim delimiter to separate KEY and VALUE, if NULL use first
* space character.
* @exception std::bad_alloc if memory for the internal strings can't be
* allocated.
* @return whether a key was found.
*
* A "#" character and everything after it are discarded and the result
* trimmed of leading and trailing white space. Use the delimiter
* character (or, if it is NULL, the first white space) to separate \e key
* and \e value. \e key and \e value are trimmed of leading and trailing
* white space. If \e key is empty, then \e value is set to "" and false
* is returned.
**********************************************************************/
static bool ParseLine(const std::string& line,
std::string& key, std::string& value,
char delim);
/**
* Parse a KEY VALUE line.
*
* @param[in] line the input line.
* @param[out] key the KEY.
* @param[out] value the VALUE.
* @exception std::bad_alloc if memory for the internal strings can't be
* allocated.
* @return whether a key was found.
*
* \note This is a transition routine. At some point \e delim will be made
* an optional argument in the previous version of ParseLine and this
* version will be removed.
**********************************************************************/
static bool ParseLine(const std::string& line,
std::string& key, std::string& value);
/**
* Set the binary precision of a real number.
*
* @param[in] ndigits the number of bits of precision. If ndigits is 0
* (the default), then determine the precision from the environment
* variable GEOGRAPHICLIB_DIGITS. If this is undefined, use ndigits =
* 256 (i.e., about 77 decimal digits).
* @return the resulting number of bits of precision.
*
* This only has an effect when GEOGRAPHICLIB_PRECISION = 5. The
* precision should only be set once and before calls to any other
* GeographicLib functions. (Several functions, for example Math::pi(),
* cache the return value in a static local variable. The precision needs
* to be set before a call to any such functions.) In multi-threaded
* applications, it is necessary also to set the precision in each thread
* (see the example GeoidToGTX.cpp).
**********************************************************************/
static int set_digits(int ndigits = 0);
};
/**
* The specialization of Utility::val<T>() for strings.
**********************************************************************/
template<> inline std::string Utility::val<std::string>(const std::string& s)
{ return trim(s); }
/**
* The specialization of Utility::val<T>() for bools.
**********************************************************************/
template<> inline bool Utility::val<bool>(const std::string& s) {
std::string t(trim(s));
if (t.empty()) return false;
bool x;
{
std::istringstream is(t);
if (is >> x) {
int pos = int(is.tellg()); // Returns -1 at end of string?
if (!(pos < 0 || pos == int(t.size())))
throw GeographicErr("Extra text " + t.substr(pos) +
" at end of " + t);
return x;
}
}
for (std::string::iterator p = t.begin(); p != t.end(); ++p)
*p = char(std::tolower(*p));
switch (t[0]) { // already checked that t isn't empty
case 'f':
if (t == "f" || t == "false") return false;
break;
case 'n':
if (t == "n" || t == "nil" || t == "no") return false;
break;
case 'o':
if (t == "off") return false;
else if (t == "on") return true;
break;
case 't':
if (t == "t" || t == "true") return true;
break;
case 'y':
if (t == "y" || t == "yes") return true;
break;
default:
break;
}
throw GeographicErr("Cannot decode " + t + " as a bool");
}
} // namespace GeographicLib
#if defined(_MSC_VER)
# pragma warning (pop)
#endif
#endif // GEOGRAPHICLIB_UTILITY_HPP