hh-suite-3.3.0/src/util-inl.h

/*
 * util-inl.h
 *
 *  Created on: Mar 28, 2014
 *      Author: meiermark
 */

#ifndef UTIL_INL_H_
#define UTIL_INL_H_

#include <cstdlib>

//// max and min
inline double dmax(double x, double y) {
  return (x > y ? x : y);
}
inline double dmin(double x, double y) {
  return (x < y ? x : y);
}
inline int imax(int x, int y) {
  return (x > y ? x : y);
}
inline int imin(int x, int y) {
  return (x < y ? x : y);
}
inline int iabs(int x) {
  return (x >= 0 ? x : -x);
}

// Rounding up, rounding down and rounding to nearest integer
inline int iceil(double x) {
  return int(ceil(x));
}
inline int ifloor(double x) {
  return int(floor(x));
}
inline int iround(double x) {
  return int(floor(x + 0.5));
}

//// Generalized mean: d=0: sqrt(x*y)  d=1: (x+y)/2  d->-inf: min(x,y)  d->+inf: max(x,y)
inline double fmean(double x, double y, double d) {
  return pow((pow(x, d) + pow(y, d)) / 2, 1. / d);
}

// log base 2
inline float safe_log2(float x) {
  return (x <= 0 ? (float) (-100000) : 1.442695041 * log(x));
}
inline float safe_log10(float x) {
  return (x <= 0 ? (float) (-100000) : 0.434294481 * log(x));
}

/////////////////////////////////////////////////////////////////////////////////////
// fast log base 2
/////////////////////////////////////////////////////////////////////////////////////

// Fast log2
// ATTENTION: need to compile with g++ -fno-strict-aliasing when using -O2 or -O3!!!
// Maximum deviation: +/- 2.1E-5
// Run time: ~1.2E-8s on Intel core2 2.13GHz, log2(): 5.4E-8s
// For a negative argument, -128 is returned.
// The function makes use of the representation of 4-byte floating point numbers:
// seee eeee emmm mmmm mmmm mmmm mmmm mmmm
// s is the sign, eee eee e gives the exponent + 127 (in hex: 0x7f).
// The following 23 bits give the mantisse, the binary digits after the decimal
// point:  x = (-1)^s * 1.mmmmmmmmmmmmmmmmmmmmmmm * 2^(eeeeeeee-127)
// Therefore,  log2(x) = eeeeeeee-127 + log2(1.mmmmmm...)
//                     = eeeeeeee-127 + log2(1+y),  where y = 0.mmmmmm...
//                     ~ eeeeeeee-127 + ((a*y+b)*y+c)*y
// The coefficients a, b  were determined by a least squares fit, and c=1-a-b to get 1 at y=1.
// Lower/higher order polynomials may be used for faster or more precise calculation:
// Order 1: log2(1+y) ~ y
// Order 2: log2(1+y) = (a*y + 1-a)*y, a=-0.3427
//  => max dev = +/- 8E-3, run time ~ ?
// Order 3: log2(1+y) = ((a*y+b)*y + 1-a-b)*y, a=0.1564, b=-0.5773
//  => max dev = +/- 1E-3, run time ~ ?
// Order 4: log2(1+y) = (((a*y+b)*y+c)*y + 1-a-b-c)*y, a=-0.0803 b=0.3170 c=-0.6748
//  => max dev = +/- 1.4E-4, run time ~ ?
// Order 5: log2(1+y) = ((((a*y+b)*y+c)*y+d)*y + 1-a-b-c-d)*y,
//     a=0.0440047 b=-0.1903190 c=0.4123442 d=-0.7077702 1-a-b-c-d=1.441740
//  => max dev = +/- 2.1E-5, run time ~ 1.2E-8s
inline float flog2(float x) {
  if (x <= 0)
    return -128;
  int *px = (int*) (&x);        // store address of float as pointer to long int
  float e = (float) (((*px & 0x7F800000) >> 23) - 0x7f); // shift right by 23 bits and subtract 127 = 0x7f => exponent
  *px = ((*px & 0x007FFFFF) | 0x3f800000);  // set exponent to 127 (i.e., 0)
  x -= 1.0;         // and calculate x-1.0
  x *= (1.441740
      + x * (-0.7077702 + x * (0.4123442 + x * (-0.1903190 + x * 0.0440047)))); // 5'th order polynomial approx. of log(1+x)
  return x + e;
}


// This function returns log2 with a max absolute deviation of +/- 1.5E-5 (typically 0.8E-5).
// It takes 0.80E-8 s  whereas log2(x) takes 5.4E-7 s. It is hence 9.4 times faster.
// It makes use of the representation of 4-byte floating point numbers:
// seee eeee emmm mmmm mmmm mmmm mmmm mmmm
// s is the sign,
// the following 8 bits, eee eee e, give the exponent + 127 (in hex: 0x7f).
// The following 23 bits give the mantisse, the binary digits after the decimal
// point:  x = (-1)^s * 1.mmmmmmmmmmmmmmmmmmmmmmm * 2^(eeeeeeee-127)
// In the code, *(int *)&x is an integer which contains the bytes as the
// floating point variable x is represented in memory. The expression
//     (((*(int *)&x) & 0x7f800000 ) >>23 )-0x7f is the exponent eeeeeeee,
// i.e., the largest integer that is smaller than log2(x) (e.g. -1 for 0.9).
inline float fast_log2(float x) {
  static float lg2[1025];         // lg2[i] = log2[1+x/1024]
  static float diff[1025]; // diff[i]= (lg2[i+1]-lg2[i])/8096 (for interpolation)
  static char initialized = 0;
  if (x <= 0)
    return -100000;
  if (!initialized)   //First fill in the arrays lg2[i] and diff[i]
  {
    float prev = 0.0f;
    lg2[0] = 0.0f;
    for (int i = 1; i <= 1024; ++i) {
      lg2[i] = log(float(1024 + i)) * 1.442695041 - 10.0f;
      diff[i - 1] = (lg2[i] - prev) * 1.2352E-4;
      prev = lg2[i];
    }
    initialized = 1;
  }
  int a = (((*((int *) &x)) & 0x7F800000) >> 23) - 0x7f; // exponent
  int b = ((*((int *) &x)) & 0x007FE000) >> 13; // first 10 bits of mantisse
  int c = ((*((int *) &x)) & 0x00001FFF);      // further 13 bits of mantisse
  return a + lg2[b] + diff[b] * (float) (c);
}

// This function returns log gamma and uses fast lookup table for computation.
// This function returns log gamma with a max abolute deviation of +/- 1E-5.
// It makes use of the representation of 4-byte floating point numbers:
// seee eeee emmm mmmm mmmm mmmm mmmm mmmm
// s is the sign,
// the following 8 bits, eee eee e, give the exponent + 127 (in hex: 0x7f).
// The following 23 bits, m, give the mantisse, the binary digits behind the decimal point.
// In summary: x = (-1)^s * 1.mmmmmmmmmmmmmmmmmmmmmm * 2^(eeeeeee-127)
// The expression (((*(int *)&x) & 0x7f800000 ) >>23 )-0x7f is the exponent eeeeeeee, i.e.
// the largest integer that is smaller than log2(x) (e.g. -1 for 0.9). *(int *)&x is an integer which
// contains the bytes as the floating point variable x is represented in memory.
// Check:  assert( sizeof(f) == sizeof(int) );
// Check:  assert( sizeof(f) == 4 );
inline float fast_log_gamma(float x) {
  static float log_gamma[1025];   // log_gamma[i] = lgammaf(1+x/1024)
  static float diff[1025]; // diff[i]= (lg2[i+1]-lg2[i])/8096 (for interpolation)
  static char initialized = 0;

  if (!initialized) {  //First fill in the arrays log_gamma[i] and diff[i]
    assert(x >= 1.0);
    assert(sizeof(x) == sizeof(int));
    assert(sizeof(x) == 4);

    float prev = 0.0f;
    log_gamma[0] = 0.0f;
    for (int i = 1; i <= 1024; ++i) {
      log_gamma[i] = lgammaf(1.0f + i * 9.765625E-4);
      diff[i - 1] = (log_gamma[i] - prev) * 1.2352E-4;
      prev = log_gamma[i];
    }
    initialized = 1;
  }

  float res = 1.0f;
  float lres = 0.0f;
  while (x >= 2.0f) {
    x -= 1.0;
    res *= x;
    if (res > 1E30) {
      lres += fast_log2(res);
      res = 1.0f;
    }
  }
  int b = ((*((int *) &x)) & 0x007FE000) >> 13; // exponent must be 0
  int c = ((*((int *) &x)) & 0x00001FFF);
  return (lres + fast_log2(res)) * 0.6931471806 + log_gamma[b]
      + diff[b] * (float) (c);
}

/////////////////////////////////////////////////////////////////////////////////////
// fast 2^x
// ATTENTION: need to compile with g++ -fno-strict-aliasing when using -O2 or -O3!!!
// Relative deviation < 4.6E-6  (< 2.3E-7 with 5'th order polynomial)
// Speed: 2.1E-8s (2.3E-8s) per call! (exp(): 8.5E-8, pow(): 1.7E-7)
// Internal representation of float number according to IEEE 754:
//   1bit sign, 8 bits exponent, 23 bits mantissa: seee eeee emmm mmmm mmmm mmmm mmmm mmmm
//                                    0x4b400000 = 0100 1011 0100 0000 0000 0000 0000 0000
//   In summary: x = (-1)^s * 1.mmmmmmmmmmmmmmmmmmmmmm * 2^(eeeeeee-127)
/////////////////////////////////////////////////////////////////////////////////////
inline float fpow2(float x)
{
  if (x>=FLT_MAX_EXP) return FLT_MAX;
  if (x<=FLT_MIN_EXP) return 0.0f;

  int *px = (int*) (&x);        // store address of float as pointer to long int
  float tx = (x - 0.5f) + (3 << 22); // temporary value for truncation: x-0.5 is added to a large integer (3<<22),
                                     // 3<<22 = (1.1bin)*2^23 = (1.1bin)*2^(150-127),
                                     // which, in internal bits, is written 0x4b400000 (since 10010110bin = 150)
  int lx = *((int*) &tx) - 0x4b400000;   // integer value of x
  float dx = x - (float) (lx);             // float remainder of x
//   x = 1.0f + dx*(0.69606564f           // cubic apporoximation of 2^x for x in the range [0, 1]
//            + dx*(0.22449433f           // Gives relative deviation < 1.5E-4
//            + dx*(0.07944023f)));       // Speed: 1.9E-8s
  x = 1.0f + dx * (0.693019f // polynomial approximation of 2^x for x in the range [0, 1]
  + dx * (0.241404f             // Gives relative deviation < 4.6E-6
  + dx * (0.0520749f            // Speed: 2.1E-8s
  + dx * 0.0134929f)));
//   x = 1.0f + dx*(0.693153f             // polynomial apporoximation of 2^x for x in the range [0, 1]
//            + dx*(0.240153f             // Gives relative deviation < 2.3E-7
//            + dx*(0.0558282f            // Speed: 2.3E-8s
//            + dx*(0.00898898f
//            + dx* 0.00187682f ))));
  *px += (lx << 23);                      // add integer power of 2 to exponent
  return x;
}

// Normalize a double array such that it sums to one
inline double normalize_to_one(double* array, size_t length,
    const float* def_array = NULL) {
  double sum = 0.0;
  for (size_t k = 0; k < length; ++k)
    sum += array[k];
  if (sum != 0.0) {
    double fac = 1.0 / sum;
    for (size_t k = 0; k < length; ++k)
      array[k] *= fac;
  }
  else if (def_array) {
    for (size_t k = 0; k < length; ++k)
      array[k] = def_array[k];
  }
  return sum;
}

// Normalize a float array such that it sums to one
inline float normalize_to_one(float* array, size_t length,
    const float* def_array = NULL) {
  float sum = 0.0;
  for (size_t k = 0; k < length; k++)
    sum += array[k];
  if (sum != 0.0) {
    float fac = 1.0 / sum;
    for (size_t k = 0; k < length; k++)
      array[k] *= fac;
  }
  else if (def_array) {
    for (size_t k = 0; k < length; ++k)
      array[k] = def_array[k];
  }
  return sum;
}

// Check if given filename is a regular file
inline bool is_regular_file(const char *fn) {
  bool ret = false;
  struct stat fstats;
  if (stat(fn, &fstats) == 0)
    if (S_ISREG(fstats.st_mode))
      ret = true;

  return ret;
}

// Check if given path is a directory
inline bool is_directory(const char *fn) {
  bool ret = false;
  struct stat fstats;
  if (stat(fn, &fstats) == 0)
    if (S_ISDIR(fstats.st_mode))
      ret = true;

  return ret;
}

// Normalize a float array such that it sums to one
// If it sums to 0 then assign def_array elements to array (optional)
inline float NormalizeTo1(float* array, int length, const float* def_array = NULL) {
  float sum = 0.0f;
  int k;
  for (k = 0; k < length; k++)
    sum += array[k];
  if (sum != 0.0f) {
    float fac = 1.0 / sum;
    for (k = 0; k < length; k++)
      array[k] *= fac;
  }
  else if (def_array)
    for (k = 0; k < length; k++)
      array[k] = def_array[k];
  return sum;
}

// Normalize a float array such that it sums to x
// If it sums to 0 then assign def_array elements to array (optional)
inline float NormalizeToX(float* array, int length, float x, float* def_array =
    NULL) {
  float sum = 0.0;
  int k;
  for (k = 0; k < length; k++)
    sum += array[k];
  if (sum) {
    float fac = x / sum;
    for (k = 0; k < length; k++)
      array[k] *= fac;
  }
  else if (def_array)
    for (k = 0; k < length; k++)
      array[k] = def_array[k];
  return sum;
}

/////////////////////////////////////////////////////////////////////////////////////
// String utilities
/////////////////////////////////////////////////////////////////////////////////////

// Safe strcpy command that limits copy to a maximum of maxlen+1 characters
// including the '\0' character.
// (Different from standard strncpy, which pads with \0 characters)
// Returns maxlen minus the number of non-\0 characters copied
// If the string is cut prematurely it will return 0!
inline int strmcpy(char* dest, const char* source, size_t maxlen) {
  while (*source && (maxlen--) > 0)
    *dest++ = *source++;
  *dest = '\0';
  return maxlen;
}

// Scans string for integer number starting from ptr and returns this number.
// The ptr will then be moved to the first position after the integer number.
// If no integer number is found, it returns INT_MIN and sets ptr to NULL.
inline int strtoi(const char*& ptr) {
  int i;
  const char* ptr0 = ptr;
  if (!ptr)
    return INT_MIN;
  while (*ptr != '\0' && !(*ptr >= '0' && *ptr <= '9'))
    ptr++;
  if (*ptr == '\0') {
    ptr = 0;
    return INT_MIN;
  }
  if (*(ptr - 1) == '-' && ptr > ptr0)
    i = -atoi(ptr);
  else
    i = atoi(ptr);
  while (*ptr >= '0' && *ptr <= '9')
    ptr++;
  return i;
}

//Same as strint, but interpretes '*' as default
inline int strtoi_(const char*& ptr, int deflt = INT_MAX) {
  int i;
  if (!ptr)
    return INT_MIN;
  while (*ptr != '\0' && !(*ptr >= '0' && *ptr <= '9') && *ptr != '*')
    ptr++;
  if (*ptr == '\0') {
    ptr = 0;
    return INT_MIN;
  }
  if (*ptr == '*') {
    ptr++;
    return deflt;
  }
  if (*(ptr - 1) == '-')
    i = atoi(ptr - 1);
  else
    i = atoi(ptr);
  while (*ptr >= '0' && *ptr <= '9')
    ptr++;
  return i;
}


// Removes the newline and other control characters at the end of a string (if present)
// and returns the new length of the string (-1 if str is NULL)
inline int chomp(char str[]) {
  if (!str)
    return -1;
  int l = 0;
  for (l = strlen(str) - 1; l >= 0 && str[l] < 32; l--)
    ;
  str[++l] = '\0';
  return l;
}

// Emulates the ifstream::getline method; similar to fgets(str,maxlen,FILE*),
// but removes the newline at the end and returns NULL if at end of file or read error
inline char* fgetline(char str[], const int maxlen, FILE* file) {
  if (!fgets(str, maxlen, file))
    return NULL;
  if (chomp(str) + 1 >= maxlen)    // if line is cut after maxlen characters...
    while (fgetc(file) != '\n')
      ; // ... read in rest of line

  return (str);
}

// Returns pointer to first non-white-space character in str OR to NULL if none found
inline char* strscn(char* str) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr <= 32)
    ptr++;
  return (*ptr == '\0') ? NULL : ptr;
}

// Returns pointer to first white-space character in str OR to NULL if none found
inline char* strscn_ws(char* str) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr > 32)
    ptr++;
  return (*ptr == '\0') ? NULL : ptr;
}

//Returns pointer to first non-white-space character in str OR to NULL if none found
inline const char* strscn_c(const char* str) {
  if (!str)
    return NULL;
  const char* ptr = str;
  while (*ptr != '\0' && isspace(*ptr))
    ptr++;
  return (*ptr == '\0') ? NULL : ptr;
}

// Returns pointer to first  non-white-space character in str OR to end of string '\0' if none found
inline char* strscn_(char* str) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr <= 32)
    ptr++;
  return ptr;
}

// Returns pointer to first non-c character in str OR to NULL if none found
inline char* strscn(char* str, const char c) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr == c)
    ptr++;
  return (*ptr == '\0') ? NULL : ptr;
}

// Returns pointer to first  non-c character in str OR to end of string '\0' if none found
inline char* strscn_(char* str, const char c) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr == c)
    ptr++;
  return ptr;
}

// Cuts string at first white space character found by overwriting it with '\0'.
// Returns pointer to next non-white-space char OR to NULL if no such char found
inline char* strcut(char* str) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr > 32)
    ptr++;
  if (*ptr == '\0')
    return NULL;
  *ptr = '\0';
  ptr++;
  while (*ptr != '\0' && *ptr <= 32)
    ptr++;
  return (*ptr == '\0') ? NULL : ptr;
}

// Cuts string at first white space character found by overwriting it with '\0'.
// Returns pointer to next non-white-space char OR to end of string '\0' if none found
inline char* strcut_(char* str) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr > 32)
    ptr++;
  if (*ptr == '\0')
    return ptr;
  *ptr = '\0';
  ptr++;
  while (*ptr != '\0' && *ptr <= 32)
    ptr++;
  return ptr;
}

// Cuts string at first occurence of charcter c, by overwriting it with '\0'.
// Returns pointer to next char not equal c, OR to NULL if none found
inline char* strcut(char* str, const char c) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr != c)
    ptr++;
  if (*ptr == '\0')
    return NULL;
  *ptr = '\0';
  ptr++;
  while (*ptr != '\0' && *ptr == c)
    ptr++;
  return (*ptr == '\0') ? NULL : ptr;
}

// Cuts string at first occurence of charcter c, by overwriting it with '\0'.
// Returns pointer to next char not equal c, OR to end of string '\0' if none found
inline char* strcut_(char* str, const char c) {
  if (!str)
    return NULL;
  char* ptr = str;
  while (*ptr != '\0' && *ptr != c)
    ptr++;
  if (*ptr == '\0')
    return ptr;
  *ptr = '\0';
  ptr++;
  while (*ptr != '\0' && *ptr == c)
    ptr++;
  return ptr;
}

// Cuts string at first occurence of substr, by overwriting the first letter with '\0'.
// Returns pointer to next char after occurence of substr, OR to NULL if no such char found
inline char* strcut(char* str, const char* substr) {
  char* ptr;     //present location in str being compared to substr
  const char* sptr = substr; //present location in substr being compared to substr
  // while not at end of str and not all of substr is matched yet
  while (1) {
    for (ptr = str, sptr = substr; *ptr == *sptr && *ptr != '\0'; ptr++, sptr++)
      ;
    if (*sptr == '\0') {
      *str = '\0';
      return ptr;
    }
    if (*ptr == '\0')
      return NULL;
    str++;
  }
}

// Cuts string at first occurence of substr, by overwriting the first letter with '\0'.
// Returns pointer to next char after occurence of substr, OR to end of string '\0' if no such char found
inline char* strcut_(char* str, const char* substr) {
  char* ptr;         //present location in str being compared to substr
  const char* sptr = substr; //present location in substr being compared to str
  // while not at end of str and not all of substr is matched yet
  while (1) {
    for (ptr = str, sptr = substr; *ptr == *sptr && *ptr != '\0'; ptr++, sptr++)
      ;
    if (*sptr == '\0') {
      *str = '\0';
      return ptr;
    }
    if (*ptr == '\0')
      return ptr;
    str++;
  }
}

// Copies first word in ptr to str. In other words, copies first block of non whitespace characters,
// beginning at ptr, to str. If a word is found, returns address of second word in ptr or, if no second
// word is found, returns address to end of word ('\0' character) in ptr string. If no word is found
// in ptr NULL is returned.
inline char* strwrd(char* str, char* ptr) {
  ptr = strscn(ptr);    // advance to beginning of next word
  if (ptr) {
    while (*ptr != '\0' && *ptr > 32)
      *(str++) = *(ptr++);
    *str = '\0';
    while (*ptr != '\0' && *ptr <= 32)
      ptr++;
    return ptr;
  }
  else
    return NULL;
}

// Copies first word in ptr to str. In other words, copies first block of non whitespace characters,
// beginning at ptr, to str. If a word is found, returns address of second word in ptr or, if no second
// word is found, returns address to end of word ('\0' character) in ptr string. If no word is found
// in ptr NULL is returned.
inline char* strwrd(char* str, char* ptr, int maxlen) {
  ptr = strscn(ptr);    // advance to beginning of next word
  if (ptr) {
    while (*ptr != '\0' && *ptr > 32 && (maxlen--) > 0)
      *(str++) = *(ptr++);
    *str = '\0';
    while (*ptr != '\0' && *ptr <= 32)
      ptr++;
    return ptr;
  }
  else
    return NULL;
}

// Copies first word ***delimited by char c*** in ptr to str. In other words, copies first block of non-c characters,
// beginning at ptr, to str. If a word is found, returns address of second word in ptr or, if no second
// word is found, returns address to end of word ('\0' character) in ptr string. If no word is found
// in ptr NULL is returned.
inline char* strwrd(char* str, char* ptr, const char c) {
  ptr = strscn(ptr, c);    // advance to beginning of next word
  if (ptr) {
    while (*ptr != '\0' && *ptr != c)
      *(str++) = *(ptr++);
    *str = '\0';
    while (*ptr != '\0' && *ptr == c)
      ptr++;
    return ptr;
  }
  else
    return NULL;
}

// transforms chr into an uppercase character
inline char uprchr(char chr) {
  return (chr >= 'a' && chr <= 'z') ? chr + 'A' - 'a' : chr;
}

// transforms chr into an lowercase character
inline char lwrchr(char chr) {
  return (chr >= 'A' && chr <= 'Z') ? chr - 'A' + 'a' : chr;
}

// Replaces first occurence of str1 by str2 in str. Returns pointer to first occurence or NULL if not found
// ATTENTION: if str2 is longer than str1, allocated memory of str must be long enough!!
inline char* strsubst(char* str, const char str1[], const char str2[]) {
  char* ptr = strstr(str, str1);
  strcpy(ptr, str2);
  return ptr;
}


inline char* RemovePath(char outname[], char filename[]) {
  char* ptr;
#ifdef WINDOWS
  ptr=strrchr(filename,92);  //return adress for LAST \ (backslash) in name
#else
  ptr = strrchr(filename, '/'); //return adress for LAST / in name
#endif
  if (!ptr)
    ptr = filename;
  else
    ptr++;
  strcpy(outname, ptr);
  return outname;
}

inline char* RemoveExtension(char outname[], char filename[]) {
  char *ptr1;
  ptr1 = strrchr(filename, '.');       //return adress for LAST '.' in name
  if (ptr1) {
    *ptr1 = '\0';
    strcpy(outname, filename);
    *ptr1 = '.';
  }
  else
    strcpy(outname, filename);
  return outname;
}

inline char* Extension(char extension[], const char* filename) {
  //return adress for LAST '.' in name
  const char* ptr = strrchr(filename, '.');
  if (ptr)
    strcpy(extension, ptr + 1);
  else
    *extension = '\0';
  return extension;
}

// Path includes last '/'
inline char* Pathname(char pathname[], char filename[]) {
  char* ptr;
  char chr;
#ifdef WINDOWS
  ptr=strrchr(filename,92);  //return adress for LAST \ (backslash) in name
#else
  ptr = strrchr(filename, '/'); //return adress for LAST / in name
#endif
  if (ptr) {
    chr = *(++ptr);
    *ptr = '\0';
    strcpy(pathname, filename);
    *ptr = chr;
  }
  else
    *pathname = '\0';
  return pathname;
}

// Swaps two integer elements in array k
inline void swapi(int k[], int i, int j) {
  int temp;
  temp = k[i];
  k[i] = k[j];
  k[j] = temp;
}

inline bool file_exists(const char* name) {
  std::ifstream f(name);
  if (f.good()) {
    f.close();
    return true;
  }
  else {
    f.close();
    return false;
  }
}

#endif /* UTIL_INL_H_ */