r8row.cpp

# include <cmath>
# include <cstdlib>
# include <ctime>
# include <cstring>
# include <iomanip>
# include <iostream>

using namespace std;

# include "r8row.hpp"
//****************************************************************************80

int i4_log_10 ( int i )

//****************************************************************************80
//
//  Purpose:
//
//    I4_LOG_10 returns the integer part of the logarithm base 10 of an I4.
//
//  Example:
//
//        I  I4_LOG_10
//    -----  --------
//        0    0
//        1    0
//        2    0
//        9    0
//       10    1
//       11    1
//       99    1
//      100    2
//      101    2
//      999    2
//     1000    3
//     1001    3
//     9999    3
//    10000    4
//
//  Discussion:
//
//    I4_LOG_10 ( I ) + 1 is the number of decimal digits in I.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    04 January 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int I, the number whose logarithm base 10 is desired.
//
//    Output, int I4_LOG_10, the integer part of the logarithm base 10 of
//    the absolute value of X.
//
{
  int i_abs;
  int ten_pow;
  int value;

  if ( i == 0 )
  {
    value = 0;
  }
  else
  {
    value = 0;
    ten_pow = 10;

    i_abs = abs ( i );

    while ( ten_pow <= i_abs )
    {
      value = value + 1;
      ten_pow = ten_pow * 10;
    }

  }

  return value;
}
//****************************************************************************80

int i4_max ( int i1, int i2 )

//****************************************************************************80
//
//  Purpose:
//
//    I4_MAX returns the maximum of two I4's.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    13 October 1998
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int I1, I2, are two integers to be compared.
//
//    Output, int I4_MAX, the larger of I1 and I2.
//
{
  int value;

  if ( i2 < i1 )
  {
    value = i1;
  }
  else
  {
    value = i2;
  }
  return value;
}
//****************************************************************************80

int i4_min ( int i1, int i2 )

//****************************************************************************80
//
//  Purpose:
//
//    I4_MIN returns the minimum of two I4's.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    13 October 1998
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int I1, I2, two integers to be compared.
//
//    Output, int I4_MIN, the smaller of I1 and I2.
//
{
  int value;

  if ( i1 < i2 )
  {
    value = i1;
  }
  else
  {
    value = i2;
  }
  return value;
}
//****************************************************************************80

int i4_power ( int i, int j )

//****************************************************************************80
//
//  Purpose:
//
//    I4_POWER returns the value of I^J.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    01 April 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int I, J, the base and the power.  J should be nonnegative.
//
//    Output, int I4_POWER, the value of I^J.
//
{
  int k;
  int value;

  if ( j < 0 )
  {
    if ( i == 1 )
    {
      value = 1;
    }
    else if ( i == 0 )
    {
      cerr << "\n";
      cerr << "I4_POWER - Fatal error!\n";
      cerr << "  I^J requested, with I = 0 and J negative.\n";
      exit ( 1 );
    }
    else
    {
      value = 0;
    }
  }
  else if ( j == 0 )
  {
    if ( i == 0 )
    {
      cerr << "\n";
      cerr << "I4_POWER - Fatal error!\n";
      cerr << "  I^J requested, with I = 0 and J = 0.\n";
      exit ( 1 );
    }
    else
    {
      value = 1;
    }
  }
  else if ( j == 1 )
  {
    value = i;
  }
  else
  {
    value = 1;
    for ( k = 1; k <= j; k++ )
    {
      value = value * i;
    }
  }
  return value;
}
//****************************************************************************80

void i4mat_print ( int m, int n, int a[], string title )

//****************************************************************************80
//
//  Purpose:
//
//    I4MAT_PRINT prints an I4MAT.
//
//  Discussion:
//
//    An I4MAT is an MxN array of I4's, stored by (I,J) -> [I+J*M].
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    10 September 2009
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows in A.
//
//    Input, int N, the number of columns in A.
//
//    Input, int A[M*N], the M by N matrix.
//
//    Input, string TITLE, a title.
//
{
  i4mat_print_some ( m, n, a, 1, 1, m, n, title );

  return;
}
//****************************************************************************80

void i4mat_print_some ( int m, int n, int a[], int ilo, int jlo, int ihi,
  int jhi, string title )

//****************************************************************************80
//
//  Purpose:
//
//    I4MAT_PRINT_SOME prints some of an I4MAT.
//
//  Discussion:
//
//    An I4MAT is an MxN array of I4's, stored by (I,J) -> [I+J*M].
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    20 August 2010
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows of the matrix.
//    M must be positive.
//
//    Input, int N, the number of columns of the matrix.
//    N must be positive.
//
//    Input, int A[M*N], the matrix.
//
//    Input, int ILO, JLO, IHI, JHI, designate the first row and
//    column, and the last row and column to be printed.
//
//    Input, string TITLE, a title.
//
{
# define INCX 10

  int i;
  int i2hi;
  int i2lo;
  int j;
  int j2hi;
  int j2lo;

  cout << "\n";
  cout << title << "\n";

  if ( m <= 0 || n <= 0 )
  {
    cout << "\n";
    cout << "  (None)\n";
    return;
  }
//
//  Print the columns of the matrix, in strips of INCX.
//
  for ( j2lo = jlo; j2lo <= jhi; j2lo = j2lo + INCX )
  {
    j2hi = j2lo + INCX - 1;
    if ( n < j2hi )
    {
      j2hi = n;
    }
    if ( jhi < j2hi )
    {
      j2hi = jhi;
    }

    cout << "\n";
//
//  For each column J in the current range...
//
//  Write the header.
//
    cout << "  Col:";
    for ( j = j2lo; j <= j2hi; j++ )
    {
      cout << "  " << setw(6) << j - 1;
    }
    cout << "\n";
    cout << "  Row\n";
    cout << "\n";
//
//  Determine the range of the rows in this strip.
//
    if ( 1 < ilo )
    {
      i2lo = ilo;
    }
    else
    {
      i2lo = 1;
    }
    if ( ihi < m )
    {
      i2hi = ihi;
    }
    else
    {
      i2hi = m;
    }


    for ( i = i2lo; i <= i2hi; i++ )
    {
//
//  Print out (up to INCX) entries in row I, that lie in the current strip.
//
      cout << setw(5) << i - 1 << ":";
      for ( j = j2lo; j <= j2hi; j++ )
      {
        cout << "  " << setw(6) << a[i-1+(j-1)*m];
      }
      cout << "\n";
    }
  }

  return;
# undef INCX
}
//****************************************************************************80

void i4vec_print ( int n, int a[], string title )

//****************************************************************************80
//
//  Purpose:
//
//    I4VEC_PRINT prints an I4VEC.
//
//  Discussion:
//
//    An I4VEC is a vector of I4's.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    14 November 2003
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int N, the number of components of the vector.
//
//    Input, int A[N], the vector to be printed.
//
//    Input, string TITLE, a title.
//
{
  int i;

  cout << "\n";
  cout << title << "\n";
  cout << "\n";
  for ( i = 0; i < n; i++ )
  {
    cout << "  " << setw(8) << i
         << ": " << setw(8) << a[i]  << "\n";
  }
  return;
}
//****************************************************************************80

int r8row_compare ( int m, int n, double a[], int i, int j )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_COMPARE compares two rows in an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Example:
//
//    Input:
//
//      M = 4, N = 3, I = 2, J = 4
//
//      A = (
//        1. 5. 9.
//        2. 6. 10.
//        3. 7. 11.
//        4. 8. 12. )
//
//    Output:
//
//      R8ROW_COMPARE = -1
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    25 May 2012
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input, double A[M*N], the M by N array.
//
//    Input, int I, J, the rows to be compared.
//    I and J must be between 0 and M - 1.
//
//    Output, int R8ROW_COMPARE, the results of the comparison:
//    -1, row I < row J,
//     0, row I = row J,
//    +1, row J < row I.
//
{
  int k;
  int value;
//
//  Check.
//
  if ( i < 0 || m <= i )
  {
    cerr << "\n";
    cerr << "R8ROW_COMPARE - Fatal error!\n";
    cerr << "  Row index I is out of bounds.\n";
    cerr << "  I = " << i << "\n";
    exit ( 1 );
  }

  if ( j < 0 || m <= j )
  {
    cerr << "\n";
    cerr << "R8ROW_COMPARE - Fatal error!\n";
    cerr << "  Row index J is out of bounds.\n";
    cerr << "  J = " << j << "\n";
    exit ( 1 );
  }

  value = 0;

  if ( i == j )
  {
    return value;
  }

  k = 0;

  while ( k < n )
  {
    if ( a[i+k*m] < a[j+k*m] )
    {
      value = -1;
      return value;
    }
    else if ( a[j+k*m] < a[i+k*m] )
    {
      value = +1;
      return value;
    }
    k = k + 1;
  }

  return value;
}
//****************************************************************************80

double *r8row_indicator_new ( int m, int n )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_INDICATOR_NEW sets up an "indicator" R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//    The value of each entry suggests its location, as in:
//
//      11  12  13  14
//      21  22  23  24
//      31  32  33  34
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    25 January 2005
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows of the matrix.
//    M must be positive.
//
//    Input, int N, the number of columns of the matrix.
//    N must be positive.
//
//    Output, double R8ROW_INDICATOR_NEW[M*N], the table.
//
{
  double *a;
  int fac;
  int i;
  int j;

  a = new double[m*n];

  fac = i4_power ( 10, i4_log_10 ( n ) + 1 );

  for ( i = 1; i <= m; i++ )
  {
    for ( j = 1; j <= n; j++ )
    {
      a[i-1+(j-1)*m] = ( double ) ( fac * i + j );
    }
  }
  return a;
}
//****************************************************************************80

double *r8row_max ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_MAX returns the row maximums of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Example:
//
//    A =
//      1  2  3
//      2  6  7
//
//    MAX =
//      3
//      7
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    29 October 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns in the array.
//
//    Input, double A[M*N], the array to be examined.
//
//    Output, double R8ROW_MAX[M], the maximums of the rows.
//
{
  int i;
  int j;
  double *amax;

  amax = new double[m];

  for ( i = 0; i < m; i++ )
  {
    amax[i] = a[i+0*m];

    for ( j = 1; j < n; j++ )
    {
      if ( amax[i] < a[i+j*m] )
      {
        amax[i] = a[i+j*m];
      }
    }
  }

  return amax;
}
//****************************************************************************80

double *r8row_mean ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_MEAN returns the row means of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Example:
//
//    A =
//      1  2  3
//      2  6  7
//
//    MEAN =
//      2
//      5
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    29 October 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns in the array.
//
//    Input, double A[M*N], the array to be examined.
//
//    Output, double R8ROW_MEAN[M], the means, or averages, of the rows.
//
{
  int i;
  int j;
  double *mean;

  mean = new double[m];

  for ( i = 0; i < m; i++ )
  {
    mean[i] = 0.0;
    for ( j = 0; j < n; j++ )
    {
      mean[i] = mean[i] + a[i+j*m];
    }
    mean[i] = mean[i] / ( double ) ( n );
  }

  return mean;
}
//****************************************************************************80

double *r8row_min ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_MIN returns the row minimums of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Example:
//
//    A =
//      1  2  3
//      2  6  7
//
//    MIN =
//      1
//      2
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    29 October 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns in the array.
//
//    Input, double A[M*N], the array to be examined.
//
//    Output, double R8ROW_MIN[M], the minimums of the rows.
//
{
  int i;
  int j;
  double *amin;

  amin = new double[m];

  for ( i = 0; i < m; i++ )
  {
    amin[i] = a[i+0*m];
    for ( j = 1; j < n; j++ )
    {
      if ( a[i+j*m] < amin[i] )
      {
        amin[i] = a[i+j*m];
      }
    }
  }

  return amin;
}
//****************************************************************************80

void r8row_print ( int m, int n, double a[], string title )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_PRINT prints an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    10 September 2009
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows in A.
//
//    Input, int N, the number of columns in A.
//
//    Input, double A[M*N], the M by N matrix.
//
//    Input, string TITLE, a title.
//
{
  r8row_print_some ( m, n, a, 1, 1, m, n, title );

  return;
}
//****************************************************************************80

void r8row_print_some ( int m, int n, double a[], int ilo, int jlo, int ihi,
  int jhi, string title )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_PRINT_SOME prints some of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    26 June 2013
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows of the matrix.
//    M must be positive.
//
//    Input, int N, the number of columns of the matrix.
//    N must be positive.
//
//    Input, double A[M*N], the matrix.
//
//    Input, int ILO, JLO, IHI, JHI, designate the first row and
//    column, and the last row and column to be printed.
//
//    Input, string TITLE, a title.
//
{
# define INCX 5

  int i;
  int i2hi;
  int i2lo;
  int j;
  int j2hi;
  int j2lo;

  cout << "\n";
  cout << title << "\n";

  if ( m <= 0 || n <= 0 )
  {
    cout << "\n";
    cout << "  (None)\n";
    return;
  }
//
//  Print the columns of the matrix, in strips of 5.
//
  for ( j2lo = jlo; j2lo <= jhi; j2lo = j2lo + INCX )
  {
    j2hi = j2lo + INCX - 1;
    if ( n < j2hi )
    {
      j2hi = n;
    }
    if ( jhi < j2hi )
    {
      j2hi = jhi;
    }
    cout << "\n";
//
//  For each column J in the current range...
//
//  Write the header.
//
    cout << "  Col:    ";
    for ( j = j2lo; j <= j2hi; j++ )
    {
      cout << setw(7) << j - 1 << "       ";
    }
    cout << "\n";
    cout << "  Row\n";
    cout << "\n";
//
//  Determine the range of the rows in this strip.
//
    if ( 1 < ilo )
    {
      i2lo = ilo;
    }
    else
    {
      i2lo = 1;
    }
    if ( ihi < m )
    {
      i2hi = ihi;
    }
    else
    {
      i2hi = m;
    }

    for ( i = i2lo; i <= i2hi; i++ )
    {
//
//  Print out (up to) 5 entries in row I, that lie in the current strip.
//
      cout << setw(5) << i - 1 << ": ";
      for ( j = j2lo; j <= j2hi; j++ )
      {
        cout << setw(12) << a[i-1+(j-1)*m] << "  ";
      }
      cout << "\n";
    }
  }

  return;
# undef INCX
}
//****************************************************************************80

void r8row_reverse ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_REVERSE reverses the order of the rows of an R8MAT.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//    To reverse the rows is to start with something like
//
//      11 12 13 14 15
//      21 22 23 24 25
//      31 32 33 34 35
//      41 42 43 44 45
//      51 52 53 54 55
//
//    and return
//
//      51 52 53 54 55
//      41 42 43 44 45
//      31 32 33 34 35
//      21 22 23 24 25
//      11 12 13 14 15
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    06 May 2013
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input/output, double A[M*N], the matrix whose rows are to be flipped.
//
{
  int i;
  int j;
  double t;

  for ( j = 0; j < n; j++ )
  {
    for ( i = 0; i < ( m / 2 ); i++ )
    {
      t            = a[    i+j*m];
      a[    i+j*m] = a[m-1-i+j*m];
      a[m-1-i+j*m] = t;
    }
  }
  return;
}
//****************************************************************************80

double *r8row_running_average ( int m, int n, double v[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_RUNNING_AVERAGE computes the running averages of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    26 February 2016
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows.
//
//    Input, int N, the number of items in each row.
//
//    Input, double V[M*N], the data.
//
//    Output, double R8ROW_RUNNING_AVERAGE[M*(N+1)], the running average.  
//    A(I,J) is the average value of V(I,1:J-1).
//
{
  double *a;
  int i;
  int j;

  a = new double[m*(n+1)];
//
//  Sum.
//
  for ( i = 0; i < m; i++ )
  {
    a[i+0*m] = 0.0;
    for ( j = 1; j < n + 1; j++ )
    {
      a[i+j*m] = a[i+(j-1)*m] + v[i+(j-1)*m];
    }
  }
//
//  Average.
//
  for ( i = 0; i < m; i++ )
  {
    for ( j = 1; j < n + 1; j++ )
    {
      a[i+j*m] = a[i+j*m] / ( double ) ( j );
    }
  }

  return a;
}
//****************************************************************************80

double *r8row_running_sum ( int m, int n, double v[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_RUNNING_SUM computes the running sum of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    26 February 2016
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, the number of rows.
//
//    Input, int N, the number of items in each row.
//
//    Input, double V[M,N], the data.
//
//    Output, double R8ROW_RUNNING_SUM[M*(N+1)], the running sums.  
//    S(I,J) is the sum of V(i,1:J-1).
//
{
  int i;
  int j;
  double *s;

  s = new double[m*(n+1)];
//
//  Sum.
//
  for ( i = 0; i < m; i++ )
  {
    s[i+0*m] = 0.0;
    for ( j = 1; j < n + 1; j++ )
    {
      s[i+j*m] = s[i+(j-1)*m] + v[i+(j-1)*m];
    }
  }

  return s;
}
//****************************************************************************80

void r8row_sort_heap_a ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_SORT_HEAP_A ascending heapsorts an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//    In lexicographic order, the statement "X < Y", applied to two real
//    vectors X and Y of length M, means that there is some index I, with
//    1 <= I <= M, with the property that
//
//      X(J) = Y(J) for J < I,
//    and
//      X(I) < Y(I).
//
//    In other words, the first time they differ, X is smaller.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    25 May 2012
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input/output, double A[M*N].
//    On input, the array of M rows of N-vectors.
//    On output, the rows of A have been sorted in lexicographic order.
//
{
  int i;
  int indx;
  int isgn;
  int j;

  if ( m <= 0 )
  {
    return;
  }

  if ( n <= 1 )
  {
    return;
  }
//
//  Initialize.
//
  i = 0;
  indx = 0;
  isgn = 0;
  j = 0;
//
//  Call the external heap sorter.
//
  for ( ; ; )
  {
    sort_heap_external ( m, indx, i, j, isgn );
//
//  Interchange the I and J objects.
//
    if ( 0 < indx )
    {
      r8row_swap ( m, n, a, i - 1, j - 1 );
    }
//
//  Compare the I and J objects.
//
    else if ( indx < 0 )
    {
      isgn = r8row_compare ( m, n, a, i - 1, j - 1 );
    }
    else if ( indx == 0 )
    {
      break;
    }
  }

  return;
}
//****************************************************************************80

double *r8row_sum ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_SUM returns the sums of the rows of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    16 September 2005
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input, double A[M*N], the M by N array.
//
//    Output, double ROWSUM[M], the sum of the entries of
//    each row.
//
{
  int i;
  int j;
  double *rowsum;

  rowsum = new double[m];

  for ( i = 0; i < m; i++ )
  {
    rowsum[i] = 0.0;
    for ( j = 0; j < n; j++ )
    {
      rowsum[i] = rowsum[i] + a[i+j*m];
    }
  }

  return rowsum;
}
//****************************************************************************80

void r8row_swap ( int m, int n, double a[], int irow1, int irow2 )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_SWAP swaps two rows of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    17 September 2003
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input/output, double A[M*N], an array of data.
//
//    Input, int IROW1, IROW2, the two rows to swap.
//    These indices should be between 0 and M - 1.
//
{
  int j;
  double t;
//
//  Check.
//
  if ( irow1 < 0 || m <= irow1 )
  {
    cerr << "\n";
    cerr << "R8ROW_SWAP - Fatal error!\n";
    cerr << "  IROW1 is out of range.\n";
    exit ( 1 );
  }

  if ( irow2 < 0 || m < irow2 )
  {
    cerr << "\n";
    cerr << "R8ROW_SWAP - Fatal error!\n";
    cerr << "  IROW2 is out of range.\n";
    exit ( 1 );
  }

  if ( irow1 == irow2 )
  {
    return;
  }

  for ( j = 0; j < n; j++ )
  {
    t            = a[irow1+j*m];
    a[irow1+j*m] = a[irow2+j*m];
    a[irow2+j*m] = t;
  }

  return;
# undef OFFSET
}
//****************************************************************************80

double *r8row_to_r8vec ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_TO_R8VEC converts an R8ROW into an R8VEC.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Example:
//
//    M = 3, N = 4
//
//    A =
//      11 12 13 14
//      21 22 23 24
//      31 32 33 34
//
//    R8ROW_TO_R8VEC = ( 11, 12, 13, 14, 21, 22, 23, 24, 31, 32, 33, 34 )
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    16 September 2005
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input, double A[M*N], the M by N array.
//
//    Output, double R8ROW_TO_R8VEC[M*N], a vector containing the M rows of A.
//
{
  int i;
  int j;
  int k;
  double *x;

  x = new double[m*n];

  k = 0;
  for ( j = 0; j < n; j++ )
  {
    for ( i = 0; i < m; i++ )
    {
      x[k] = a[i+j*m];
      k = k + 1;
    }
  }

  return x;
}
//****************************************************************************80

void r8row_transpose_print ( int m, int n, double a[], string title )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_TRANSPOSE_PRINT prints an R8ROW, transposed.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    10 September 2009
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input, double A[M*N], an M by N matrix to be printed.
//
//    Input, string TITLE, a title.
//
{
  r8row_transpose_print_some ( m, n, a, 1, 1, m, n, title );

  return;
}
//****************************************************************************80

void r8row_transpose_print_some ( int m, int n, double a[], int ilo, int jlo,
  int ihi, int jhi, string title )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_TRANSPOSE_PRINT_SOME prints some of an R8ROW, transposed.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    07 April 2014
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input, double A[M*N], an M by N matrix to be printed.
//
//    Input, int ILO, JLO, the first row and column to print.
//
//    Input, int IHI, JHI, the last row and column to print.
//
//    Input, string TITLE, a title.
//
{
# define INCX 5

  int i;
  int i2;
  int i2hi;
  int i2lo;
  int i2lo_hi;
  int i2lo_lo;
  int inc;
  int j;
  int j2hi;
  int j2lo;

  cout << "\n";
  cout << title << "\n";

  if ( m <= 0 || n <= 0 )
  {
    cout << "\n";
    cout << "  (None)\n";
    return;
  }

  if ( ilo < 1 )
  {
    i2lo_lo = 1;
  }
  else
  {
    i2lo_lo = ilo;
  }

  if ( ihi < m )
  {
    i2lo_hi = m;
  }
  else
  {
    i2lo_hi = ihi;
  }

  for ( i2lo = i2lo_lo; i2lo <= i2lo_hi; i2lo = i2lo + INCX )
  {
    i2hi = i2lo + INCX - 1;

    if ( m < i2hi )
    {
      i2hi = m;
    }
    if ( ihi < i2hi )
    {
      i2hi = ihi;
    }

    inc = i2hi + 1 - i2lo;

    cout << "\n";
    cout << "  Row: ";
    for ( i = i2lo; i <= i2hi; i++ )
    {
      cout << setw(7) << i - 1 << "       ";
    }
    cout << "\n";
    cout << "  Col\n";
    cout << "\n";

    if ( jlo < 1 )
    {
      j2lo = 1;
    }
    else
    {
      j2lo = jlo;
    }
    if ( n < jhi )
    {
      j2hi = n;
    }
    else
    {
      j2hi = jhi;
    }

    for ( j = j2lo; j <= j2hi; j++ )
    {
      cout << setw(5) << j - 1 << ":";
      for ( i2 = 1; i2 <= inc; i2++ )
      {
        i = i2lo - 1 + i2;
        cout << setw(14) << a[(i-1)+(j-1)*m];
      }
      cout << "\n";
    }
  }

  return;
# undef INCX
}
//****************************************************************************80

double *r8row_uniform_ab_new ( int m, int n, double a, double b, int &seed )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_UNIFORM_AB_NEW returns a new scaled pseudorandom R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//    This routine implements the recursion
//
//      seed = ( 16807 * seed ) mod ( 2^31 - 1 )
//      u = seed / ( 2^31 - 1 )
//
//    The integer arithmetic never requires more than 32 bits,
//    including a sign bit.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license. 
//
//  Modified:
//
//    09 April 2012
//
//  Author:
//
//    John Burkardt
//
//  Reference:
//
//    Paul Bratley, Bennett Fox, Linus Schrage,
//    A Guide to Simulation,
//    Second Edition,
//    Springer, 1987,
//    ISBN: 0387964673,
//    LC: QA76.9.C65.B73.
//
//    Bennett Fox,
//    Algorithm 647:
//    Implementation and Relative Efficiency of Quasirandom
//    Sequence Generators,
//    ACM Transactions on Mathematical Software,
//    Volume 12, Number 4, December 1986, pages 362-376.
//
//    Pierre L'Ecuyer,
//    Random Number Generation,
//    in Handbook of Simulation,
//    edited by Jerry Banks,
//    Wiley, 1998,
//    ISBN: 0471134031,
//    LC: T57.62.H37.
//
//    Peter Lewis, Allen Goodman, James Miller,
//    A Pseudo-Random Number Generator for the System/360,
//    IBM Systems Journal,
//    Volume 8, Number 2, 1969, pages 136-143.
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns.
//
//    Input, double A, B, the limits of the pseudorandom values.
//
//    Input/output, int &SEED, the "seed" value.  Normally, this
//    value should not be 0.  On output, SEED has 
//    been updated.
//
//    Output, double R8ROW_UNIFORM_AB_NEW[M*N], a matrix of pseudorandom values.
//
{
  int i;
  const int i4_huge = 2147483647;
  int j;
  int k;
  double *r;

  if ( seed == 0 )
  {
    cerr << "\n";
    cerr << "R8ROW_UNIFORM_AB_NEW - Fatal error!\n";
    cerr << "  Input value of SEED = 0.\n";
    exit ( 1 );
  }

  r = new double[m*n];

  for ( j = 0; j < n; j++ )
  {
    for ( i = 0; i < m; i++ )
    {
      k = seed / 127773;

      seed = 16807 * ( seed - k * 127773 ) - k * 2836;

      if ( seed < 0 )
      {
        seed = seed + i4_huge;
      }

      r[i+j*m] = a + ( b - a ) * ( double ) ( seed ) * 4.656612875E-10;
    }
  }

  return r;
}
//****************************************************************************80

double *r8row_variance ( int m, int n, double a[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8ROW_VARIANCE returns the variances of an R8ROW.
//
//  Discussion:
//
//    An R8ROW is an M by N array of R8's, regarded as an array of M rows,
//    each of length N.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    29 October 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int M, N, the number of rows and columns in the array.
//
//    Input, double A[M*N], the array whose variances are desired.
//
//    Output, double R8ROW_VARIANCE[M], the variances of the rows.
//
{
  int i;
  int j;
  double mean;
  double *variance;

  variance = new double[m];

  for ( i = 0; i < m; i++ )
  {
    mean = 0.0;
    for ( j = 0; j < n; j++ )
    {
      mean = mean + a[i+j*m];
    }
    mean = mean / ( double ) ( n );

    variance[i] = 0.0;
    for ( j = 0; j < n; j++ )
    {
      variance[i] = variance[i] + pow ( ( a[i+j*m] - mean ), 2 );
    }

    if ( 1 < n )
    {
      variance[i] = variance[i] / ( double ) ( n - 1 );
    }
    else
    {
      variance[i] = 0.0;
    }

  }

  return variance;
}
//****************************************************************************80

bool r8vec_eq ( int n, double a1[], double a2[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8VEC_EQ is true if every pair of entries in two R8VEC's is equal.
//
//  Discussion:
//
//    An R8VEC is a vector of R8's.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    28 August 2003
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int N, the number of entries in the vectors.
//
//    Input, double A1[N], A2[N], two vectors to compare.
//
//    Output, bool R8VEC_EQ, is TRUE if every pair of elements A1(I)
//    and A2(I) are equal, and FALSE otherwise.
//
{
  int i;

  for ( i = 0; i < n; i++ )
  {
    if ( a1[i] != a2[i] )
    {
      return false;
    }
  }
  return true;
}
//****************************************************************************80

bool r8vec_gt ( int n, double a1[], double a2[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8VEC_GT == ( A1 > A2 ) for two R8VEC's.
//
//  Discussion:
//
//    An R8VEC is a vector of R8's.
//
//    The comparison is lexicographic.
//
//    A1 > A2  <=>                              A1(1) > A2(1) or
//                 ( A1(1)     == A2(1)     and A1(2) > A2(2) ) or
//                 ...
//                 ( A1(1:N-1) == A2(1:N-1) and A1(N) > A2(N)
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    28 August 2003
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int N, the dimension of the vectors.
//
//    Input, double A1[N], A2[N], the vectors to be compared.
//
//    Output, bool R8VEC_GT, is TRUE if and only if A1 > A2.
//
{
  int i;

  for ( i = 0; i < n; i++ )
  {

    if ( a2[i] < a1[i] )
    {
       return true;
    }
    else if ( a1[i] < a2[i] )
    {
      return false;
    }

  }

  return false;
}
//****************************************************************************80

bool r8vec_lt ( int n, double a1[], double a2[] )

//****************************************************************************80
//
//  Purpose:
//
//    R8VEC_LT == ( A1 < A2 ) for two R8VEC's.
//
//  Discussion:
//
//    An R8VEC is a vector of R8's.
//
//    The comparison is lexicographic.
//
//    A1 < A2  <=>                              A1(1) < A2(1) or
//                 ( A1(1)     == A2(1)     and A1(2) < A2(2) ) or
//                 ...
//                 ( A1(1:N-1) == A2(1:N-1) and A1(N) < A2(N)
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    28 August 2003
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int N, the dimension of the vectors.
//
//    Input, double A1[N], A2[N], the vectors to be compared.
//
//    Output, bool R8VEC_LT, is TRUE if and only if A1 < A2.
//
{
  int i;

  for ( i = 0; i < n; i++ )
  {
    if ( a1[i] < a2[i] )
    {
      return true;
    }
    else if ( a2[i] < a1[i] )
    {
      return false;
    }

  }

  return false;
}
//****************************************************************************80

void r8vec_print ( int n, double a[], string title )

//****************************************************************************80
//
//  Purpose:
//
//    R8VEC_PRINT prints an R8VEC.
//
//  Discussion:
//
//    An R8VEC is a vector of R8's.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    16 August 2004
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    Input, int N, the number of components of the vector.
//
//    Input, double A[N], the vector to be printed.
//
//    Input, string TITLE, a title.
//
{
  int i;

  cout << "\n";
  cout << title << "\n";
  cout << "\n";
  for ( i = 0; i < n; i++ )
  {
    cout << "  " << setw(8)  << i
         << ": " << setw(14) << a[i]  << "\n";
  }

  return;
}
//****************************************************************************80

void sort_heap_external ( int n, int &indx, int &i, int &j, int isgn )

//****************************************************************************80
//
//  Purpose:
//
//    SORT_HEAP_EXTERNAL externally sorts a list of items into ascending order.
//
//  Discussion:
//
//    The actual list is not passed to the routine.  Hence it may
//    consist of integers, reals, numbers, names, etc.  The user,
//    after each return from the routine, will be asked to compare or
//    interchange two items.
//
//    The current version of this code mimics the FORTRAN version,
//    so the values of I and J, in particular, are FORTRAN indices.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    06 January 2013
//
//  Author:
//
//    Original FORTRAN77 version by Albert Nijenhuis, Herbert Wilf.
//    C++ version by John Burkardt
//
//  Reference:
//
//    Albert Nijenhuis, Herbert Wilf,
//    Combinatorial Algorithms,
//    Academic Press, 1978, second edition,
//    ISBN 0-12-519260-6.
//
//  Parameters:
//
//    Input, int N, the length of the input list.
//
//    Input/output, int &INDX.
//    The user must set INDX to 0 before the first call.
//    On return,
//      if INDX is greater than 0, the user must interchange
//      items I and J and recall the routine.
//      If INDX is less than 0, the user is to compare items I
//      and J and return in ISGN a negative value if I is to
//      precede J, and a positive value otherwise.
//      If INDX is 0, the sorting is done.
//
//    Output, int &I, &J.  On return with INDX positive,
//    elements I and J of the user's list should be
//    interchanged.  On return with INDX negative, elements I
//    and J are to be compared by the user.
//
//    Input, int ISGN. On return with INDX negative, the
//    user should compare elements I and J of the list.  If
//    item I is to precede item J, set ISGN negative,
//    otherwise set ISGN positive.
//
{
  static int i_save = 0;
  static int j_save = 0;
  static int k = 0;
  static int k1 = 0;
  static int n1 = 0;
//
//  INDX = 0: This is the first call.
//
  if ( indx == 0 )
  {

    i_save = 0;
    j_save = 0;
    k = n / 2;
    k1 = k;
    n1 = n;
  }
//
//  INDX < 0: The user is returning the results of a comparison.
//
  else if ( indx < 0 )
  {
    if ( indx == -2 )
    {
      if ( isgn < 0 )
      {
        i_save = i_save + 1;
      }
      j_save = k1;
      k1 = i_save;
      indx = -1;
      i = i_save;
      j = j_save;
      return;
    }

    if ( 0 < isgn )
    {
      indx = 2;
      i = i_save;
      j = j_save;
      return;
    }

    if ( k <= 1 )
    {
      if ( n1 == 1 )
      {
        i_save = 0;
        j_save = 0;
        indx = 0;
      }
      else
      {
        i_save = n1;
        j_save = 1;
        n1 = n1 - 1;
        indx = 1;
      }
      i = i_save;
      j = j_save;
      return;
    }
    k = k - 1;
    k1 = k;
  }
//
//  0 < INDX: the user was asked to make an interchange.
//
  else if ( indx == 1 )
  {
    k1 = k;
  }

  for ( ; ; )
  {

    i_save = 2 * k1;

    if ( i_save == n1 )
    {
      j_save = k1;
      k1 = i_save;
      indx = -1;
      i = i_save;
      j = j_save;
      return;
    }
    else if ( i_save <= n1 )
    {
      j_save = i_save + 1;
      indx = -2;
      i = i_save;
      j = j_save;
      return;
    }

    if ( k <= 1 )
    {
      break;
    }

    k = k - 1;
    k1 = k;
  }

  if ( n1 == 1 )
  {
    i_save = 0;
    j_save = 0;
    indx = 0;
    i = i_save;
    j = j_save;
  }
  else
  {
    i_save = n1;
    j_save = 1;
    n1 = n1 - 1;
    indx = 1;
    i = i_save;
    j = j_save;
  }

  return;
}
//****************************************************************************80

void timestamp ( )

//****************************************************************************80
//
//  Purpose:
//
//    TIMESTAMP prints the current YMDHMS date as a time stamp.
//
//  Example:
//
//    31 May 2001 09:45:54 AM
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license.
//
//  Modified:
//
//    08 July 2009
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    None
//
{
# define TIME_SIZE 40

  static char time_buffer[TIME_SIZE];
  const struct std::tm *tm_ptr;
  size_t len;
  std::time_t now;

  now = std::time ( NULL );
  tm_ptr = std::localtime ( &now );

  len = std::strftime ( time_buffer, TIME_SIZE, "%d %B %Y %I:%M:%S %p", tm_ptr );

  std::cout << time_buffer << "\n";

  return;
# undef TIME_SIZE
}