ref1.4.c - Reflectivity Curve Function

What is ref1.4.c?

    ref1.4.c is a C-Plot function that calculates the reflectivity curve for a given set of parameters supplied by parameters.dat in the current directory.

• This function requires cplx.h to compile.  cplx.h is an include file for complex number data types and functions.
• Ref1 sends 201 points to C-Plot.  The range is determined by the current x-axis range.
• initParam() loads the parameters from the data file.  See below for what the parameters mean.
• The macros that talk to C-Plot are from p_funct.h.  These macros are set_x, set_y, get_xmax(), etc.  Descriptions of them are found in the C-Plot user manual.
• The format for parameters.dat is included in parameters.dat.

P(1) - A scale for Q_z.  Usually equal to 1.
P(2) - Surface roughness
P(3) - A scale for y.  Usually equal to 1.
P(4) - Electron density of the subphase.
P(5) - Absorbtion coefficient.  Usually equal to 0.
P(6+3j) - Thickness of the layer.  (j=0 corresponds to the first layer)
P(7+3j) - Electron density of the layer.
P(8+3j) - Absorbtion coefficient of the layer.  Usually equal to 0.

C(1) - The number of layers.
C(2) - 0 for reflectivity calculations, 1 for real space calculations.
C(3) - 0 for linear calculations, 1 for logrithmic calculations.
C(4) -
C(5) - The k vector for x-rays.
C(6) - 1 to divide by Fresnel reflectivity, 0 if not.
C(7) - 0 for x-rays, 1 for neutrons.
C(8) - 1 for phase output, 0 for normal.

Michael S Kelley