*ASSIGN <n> <st> <sp>|Assigns basis set <n> to a site,spectrum
*AXIAL <tensor>|Set <tensor> (R, g, or A) to axial representation
*BASIS <filename>|Read in pruned basis as <filename>.ind
*CALL <filename>|Opens <filename> as input stream for NLSL commands
*CARTESIAN <tensor>|Set <tensor> (R, g, or A) to cartesian representation
*CONFIDENCE <val>|Set confidence level (0 to 1) for error estimates
*CORRELATION|Report correlation matrix
*DATA <filename>|Read in data file <filename>.dat
>ASCII|Read ASCII datafile
>BINARY|Read PC-GENPLOT binary file
>BCMODE <n>|Baseline-correct data by fitting a line to <n> endpoints
>DERIV <n>|Derivative mode of data (0 or 1)
>NSPLINE <n>|Spline data to <n> points
>SHIFT|Shift calculated spectrum to overlap w/ data
>NOSHIFT|Don't shift calculated spectrum to overlap w/ data
>NORM|Normalize to (double) integral of spectrum
>NONORM|Don't normalize spectrum 
>WRITE|Force output of data/fit in <dataID>.spc files
*DELETE <n> or <name>|Delete specified basis set from the buffer
*ECHO ON/OFF/<text>|Turn command echo on/or or echo text line to screen
*EXIT|Exit NLSL program
*FIT|Initiate nonlinear least-squares fitting procedure
>BOUND <scale>|Scaling factor for initial trust-region boundary
>CTOL <tol>|Tolerance (0 to 1) for determining a significant component
>FTOL <tol>|Tolerance for chi-squared convergence of least-squares
>GTOL <tol>|Tolerance for gradient (curvature) fitting convergence
>ITERATES|Output calculated function at each iteration (nlsfun.nnn)
>JACOBI|Produce files containing Jacobian for each iteration
>MAXFUN <n>|Maximum allowed function (spectrum) calculations
>MAXITR <n>|Maximum allowed iterations of least-squares procedure
>NEG|Allow negative scale factors in fit
>NONEG|Do not allow negative scale factors in fit
>NOSHIFT|Disable spectral shifting during fit
>SHIFT|Enable spectral shifting during fit
>TRACE|Produce "trace" file for fitting procedure
>TRIDIAG|Produce output of tridiagonal matrices per iteration (nlstri.nnn)
>UNWEIGHTED|Fit using rms deviation unscaled by spectral noisse
>WEIGHTED|Fit using true weighted chi-squared
>WRITE|Write spectrum fit file on termination
>XTOL <tol>|Tolerance for parameter convergence of least-squares
*FIX <parameter>|Remove parameter from list of fitting parameters
*HELP <subj> <keywrd>|Brief description of command and keyword
*LET <name>=<val>|Assign value <val> to parameter <name>
*LOG <filename>|Open <filename>.log as a logfile for the NLSL session
*PARMS (<filename>)|Print all parameter values to screen or <filename> 
*QUIT|Exit NLSL program
*READ <filename>|Opens <filename> as input stream for NLSL commands
*RESET|Clear data and parameter arrays, restoring conditions on entry
*SCALE <n> <val>/FIX/AUTO|Set constant scale factor for site n
*SEARCH <parm>|1-D Brent's method minimization of <parm>
*SERIES <parm>=<vals>|Defines a set of spectra to be fit
*SHIFT <n> <val>/ON/OFF|Set constant shift for spectrum n
*SITES <n>|Sets number of different EPR sites per spectrum
*SPHERICAL <tensor>|Set <tensor> (R, g, or A) to spherical representation
*STATUS fit/bas/data|Print out status of memory structures or fit
*VARY <par>|Add <par> to list of fitting parameters
>SCALE <scale>|Sets scale for given parameter
>FDSTEP <step>|Sets relative step for derivative calculation
*WRITE|Write displayed data to <dataID>.spc files
*VARIABLES|Floating-point variables for EPR calculation
>PHASE|Phase of spectrum (dispersion=90)
>WINT0|Isotropic inhomogeneous linewidth
>WINT2|Psi-dependent inhomogeneous linewidth
>GXX|x-component of g-tensor (cartesian)
>GYY|y-component of g-tensor (cartesian)
>GZZ|z-component of g-tensor (cartesian)
>G1|0,0 (isotropic) spherical component of g-tensor
>G2|2,0 (axial) spherical component of g-tensor
>G3|2,2 (rhombic) component of g-tensor
>GPRP|perpendicular component of axial g-tensor
>GRHM|rhombic distortion of axial g-tensor
>GPLL|parallel component of axial g-tensor
>AXX|x-component of g-tensor (cartesian)
>AYY|y-component of g-tensor (cartesian)
>AZZ|z-component of g-tensor (cartesian)
>A1|0,0 (isotropic) spherical component of g-tensor
>A2|2,0 (axial) spherical component of g-tensor
>A3|2,2 (rhombic) component of g-tensor
>APRP|perpendicular component of axial g-tensor
>ARHM|rhombic distortion of axial g-tensor
>APLL|parallel component of axial g-tensor
>RX|x-component of rotational diffusion tensor
>RY|y-component of rotational diffusion tensor
>RZ|z-component of rotational diffusion tensor
>RBAR|average rot'l diffusion rate = (Rx Ry Rz)^1/3
>N|Rotional anisotropy = 2*Rz/(Rx+Ry)
>NXY|Ratio of Rx/Ry
>RPRP|Perpendicular component of axial diffusion tensor
>RRHM|Rhombic distortion of axial diffusion = Rx/Ry
>RPLL|Perpendicular component of axial diffusion tensor
>PML|Model-dependent diffusion parameter: z rotation
>PMXY|Model-dependent diffusion parameter: xy rotation
>PMZZ|Model-dependent diffusion parameter: internal z rot'n
>DJF|Rate of jumping among <ist>-symmetric sites
>DJFPRP|Perpendicular component for anisotropic viscosity model
>OSS|Heisenberg spin-exchange rate 
>PSI|Director tilt angle
>ALPHAD|Alpha Euler angle for diffusion tilt 
>BETAD|Beta Euler angle for diffusion tilt 
>GAMMAD|gamma Euler angle for diffusion tilt 
>ALPHAM|Alpha Euler angle for magnetic tilt 
>BETAM|Beta Euler angle for magnetic tilt 
>GAMMAM|Gamma Euler angle for magnetic tilt 
>C20|Y(2,0) coefficient of orienting potential
>C22|Y(2,2) coefficient of orienting potential
>C40|Y(4,0) coefficient of orienting potential
>C42|Y(4,2) coefficient of orienting potential
>C44|Y(4,4) coefficient of orienting potential
>B0|Spectrometer field
>CGTOL|Tolerance for conjugate gradient convergence
>SHIFTR|Real part of diagonal shift for SLE matrix
>SHIFTI|Real part of diagonal shift for SLE matrix
*INTEGERS|Integer parameters for EPR calculation
>IN2|Twice the nuclear spin
>IPDF|Diffusion model (0=Brown,1=non-Brown,2=aniso.visc.)
>IST|Number of symmetry-related sites for discrete jump
>ML|0/1 for jump/free diffusion around molecular z
>MXY|0/1 for jump/free diffusion around molecular x,y
>MZZ|0/1 for jump/free INTERNAL diffusion around molecular z
>LEMX|Maximum index for even L-values in basis 
>LOMX|Maximum index for odd L-values in basis 
>KMX|Maximum index for K-values in basis 
>KMN|Minimum index for K-values in basis 
>MMX|Maximum index for M-values in basis 
>MMN|Minimum index for M-values in basis 
>IPNMX|Maximum index for pI values in basis 
>NSTEP|Number of steps in CG matrix solution
