32v 1m spline

SPLINE(1G) UNIX Programmer's Manual SPLINE(1G)

NAME

    spline - interpolate smooth curve

SYNOPSIS

    spline [ option ] ...

DESCRIPTION

    _S_p_l_i_n_e takes pairs of numbers from the standard input as
    abcissas and ordinates of a function.  It produces a similar
    set, which is approximately equally spaced and includes the
    input set, on the standard output.  The cubic spline output
    (R. W. Hamming, _N_u_m_e_r_i_c_a_l _M_e_t_h_o_d_s _f_o_r _S_c_i_e_n_t_i_s_t_s _a_n_d
    _E_n_g_i_n_e_e_r_s, 2nd ed., 349ff) has two continuous derivatives,
    and sufficiently many points to look smooth when plotted,
    for example by _g_r_a_p_h(1).

    The following options are recognized, each as a separate
    argument.

    -a   Supply abscissas automatically (they are missing from
         the input); spacing is given by the next argument, or
         is assumed to be 1 if next argument is not a number.

    -k   The constant _k used in the boundary value computation

            (2nd deriv. at end) = k*(2nd deriv. next to end)

         is set by the next argument.  By default _k = 0.

    -n   Space output points so that approximately _n intervals
         occur between the lower and upper _x limits.  (Default _n
         = 100.)

    -p   Make output periodic, i.e. match derivatives at ends.
         First and last input values should normally agree.

    -x   Next 1 (or 2) arguments are lower (and upper) _x limits.
         Normally these limits are calculated from the data.
         Automatic abcissas start at lower limit (default 0).

SEE ALSO

    graph(1)

DIAGNOSTICS

    When data is not strictly monotone in _x, _s_p_l_i_n_e reproduces
    the input without interpolating extra points.

BUGS

    A limit of 1000 input points is enforced silently.