





SPECPR Users' Manual                                            Page 8-f23.1


_F_2_3: _M_a_t_h_e_m_a_t_i_c_a_l _P_a_r_s_e_r                                      _A_l_i_a_s: _p_a_r_s[_e]

     This routine allows the user to type in arbitrary mathematical  expres-
sions  involving  data  sets  and constants. The expressions allowed are any
combination of addition, subtraction, multiplication, division, and exponen-
tiation (exponentiation is represented by ^).

     _W_A_R_N_I_N_G: f23 is site specific because of  the  interdependency  between
Fortran  and C so it may not be linked at all sites.  Check with your system
administrator.

     To use f23 type from math operations:

              _f_2_3
or
              _f_2_3_e

if errors are to be included in the computation. The program will  list  the
wavelength  data  set and the number of channels it will be using. To change
the wavelength record at this point type the file ID (upper  case)  and  the
record  number  of the new wavelength set.  If the default wavelength set is
acceptable just type a carriage return.  If you wish to  abort  the  routine
type

              _e
or
              _x

After choosing the appropriate wavelength set the routine will print out the
current  file  protections  and  allow  you  to type in the expression to be
evaluated.  For example, if you wanted to add data set  v21  to  a  Gaussian
with a height of -1.5, half width of 2.3 microns (at 1/e point), centered at
1.32 microns you would type:

              _v_2_1+-_1._5*_2._7_1_8_2_8_e_0^(-((_v_3-_1._3_2)/_2._3)^_2)

assuming you are using wavelength set v3  (note  that  the  wavelengths  are
treated as data here, so the wavelength set uses a lower case file ID).
















