A..1 Scalar Naming Conventions

The tables below list the commonly used scalars and text strings Program Variables, giving a very brief description of the expected meaning for the variables and the commands that use this variable either as input or output. More details about the meaning and use of these variables can be found in the entry for each command.

General and System Variables
Program Variable	Description	Used in Commands
$column_label	data column label	read_data()
$commentchar	comment character	read_data(), write_data()
&echo_lines	number of lines to echo()	echo(), load()
$filename	file name for input	read_data()
$group	default group name	many
$history_file	name command history file	history()
$&install_dir	installation directory	f1f2()
&pause_ignore	ignore pause() commands	pause()
&screen_echo	screen echo setting	echo(), log(), macro()
&sync_level	synchronization level	save(), set(), show()
$1 ...$9	macro arguments	at macro execution
Plotting
Program Variable	Description	Used in Commands
cursor_x	cursor x coordinate	cursor(), zoom()
cursor_y	cursor y coordinate	cursor(), zoom()
$plot_device	plotting device	plot()
$plot_file	filename for hardcopy plot	plot()
$plot_title	title for plot	plot()
$plot_xlabel	label for x-axis	plot()
$plot_ylabel	label for y-axis	plot()
FEFF Paths
Program Variable	Description	Used in Commands
$feff_file	name of FEFF file	path()
path_index	path index	path()
reff	R of a FEFF path	get_path()

Pre-Edge and Spline
Used in commands pre_edge(), and spline()
Program Variable	Description	Used in Commands
e0	E0, where k = 0
edge_step	$\Delta$$\mu$(E0), edge step
norm_c0	normaliztion parameter
norm_c1	normaliztion parameter
norm_c2	normaliztion parameter
norm1	normalization range
norm2	normalization range
norm_order	order of normalization polynomial
pre_offset	offset of pre-edge line
pre_slope	slope of pre-edge line
pre1	pre-edge range
pre2	pre-edge range
rbkg	Rbkg for XAFS spline	spline()
(see also Fourier transform parameters for spline())
Fourier Transform
Used in commands chi_noise(), feffit(), fftf(), and fftr()
Program Variable	Description	Used in Commands
$altwindow	alternate window array
dk1	dk1
dk2	dk2
dr1	dR1
dr2	dR2
kmax	kmax
kmin	kmin
kweight	k-weight w
kwindow	k $\rightarrow$ R window type
rmax	Rmax
rmin	Rmin
rwindow	R $\rightarrow$ q window type
dk1_spl	dk1	spline()
dk2_spl	dk2	spline()
kmax_spl	kmax	spline()
kmin_spl	kmin	spline()
kweight_spl	k-weight w	spline()

Fitting
Program Variable	Description	Used in Commands
chi_square	fit statistic	feffit(), minimize()
chi_reduced	fit statistic	feffit(), minimize()
epsilon_k	$\epsilon_{k}^{}$, uncertainty in $\chi$(k)	chi_noise(), feffit()
epsilon_r	$\epsilon_{R}^{}$, uncertainty in $\tilde{\chi}$(R)	chi_noise(), feffit()
&fit_iteration	number of fit interations	feffit(), minimize()
$fit_space	fitting space	feffit()
n_idp	Nidp	feffit()
n_varys	number of variables	feffit(), minimize()
r_factor	fit statistic	feffit()