PDFFIT allows the usage of variables. The general variables
i[n], r[n] and res[n] are explained in the 'command language'
section of the online help (-> command language). The variables
marked with RO below are READONLY.
x[n] : x-position of atom n of current phase (-> phase) y[n] : y-position of atom n of current phase (-> phase) z[n] : z-position of atom n of current phase (-> phase) m[n] : Number of atom type on site n (current phase) u[6,n] : Aniso. thermal factor U(ij) for site n (curr. phase) o[n] : Occupancy of site n (current phase) lat[6] : Lattice parameters (a,b,c,alpha,beta,gamma) f. phase delt[n] : Value of DELTA (sharpening !) for phase 'n' rcut[n] : Cutoff r-value for additional sharpening for phase 'n' srat[n] : Ratio of peak width below and above 'rcut' for phase 'n' csca[n] : Value of scaling factor for phase 'n' qsig[s] : Value of QSIGMA (resolution dampening) for data set 's' dsca[s] : Value of scaling factor for data set 's' dx[n] : Standard deviation of x-position dy[n] : Standard deviation of y-position dz[n] : Standard deviation of z-position du[6,n] : Standard deviation of u[6,n] (RO) do[n] : Standard deviation of o[n] (RO) dlat[6] : Standard deviation of lat[6] ddelt[n] : Standard deviation of delt[n] (RO) dsrat[n] : Standard deviation of srat[n] (RO) dcsca[n] : Standard deviation of csca[n] (RO) ddsca[s] : Standard deviation of dsca[s] (RO) dqsig[s] : Standard deviation of qsig[s] (RO) n[1] : Total number of atoms of current phase (RO) n[2] : Number of different atoms of current phase (RO) n[3] : Number of atoms per unit cell (current phase) (RO) n[4] : Number of phases (RO) n[5] : Number of current phase (change with -> phase) (RO) n[6] : Number of loaded experimental PDFs (RO) n[7] : Number of possible parameters (RO) n[8] : Number of used refinement parameters (RO) p[n] : Value of fit parameter n dp[n] : Value of standard deviation for parameter n (RO) pf[n] : Refinement flag for parameter n, 1=refine 0=fixed cl[n,m] : Correlation matrix element n,m (RO) rw[1] : expected R-value (after refinement) (RO) rw[2] : achieved R-value (after refinement) (RO) rw[3] : achieved weighted R-value (after refinement) (RO) np[s] : Number of data points of data set 's' (RO) pc[n,s] : Value of calculated PDF point 'n' of data set 's' po[n,s] : Value of observed PDF point 'n' of data set 's' pw[n,s] : Weight for PDF point 'n' of data set 's' delr[s] : Value of DELTAR of data set 's' qmax[s] : Value of QMAX for data set 's' rang[2,s] : Value of minimum (1) and maximum (2) R for refinement rmin[s] : Value of maximum R of data set 's' rmax[s] : Value of maximum R of data set 's' fa[i,s,p] : Value of matrix A(i,s,p) (see Users Guide) fb[i,s,p] : Value of matrix B(i,s,p) fc[p,dp] : Value of matrix C(p,dp)