LINEAR.exe - is a code to linearize cross sections. ENDF/B allows cross sections to be represented as tables of data points using a number of different interpolation laws between tabulated points. The subsequent use of the data can be greatly simplified and the accuracy of results improved by first linearizing all of the cross sections, i.e., replace the original tabulated data points and interpolation law by a new table where one can use linearly interpolation between tabulated points to within any required accuracy.

The first version of LINEAR was developed by D.E. Cullen in May 1974, the last one - in January 2015. On our site we present the last version for work on PC under MSDOS (WINDOWS).

A task input file has to be named LINEAR.inp, information about process of work this code is registered in report output file LINEAR.lst, the ENDF formatted input file is not changed, the resulting linearized cross sections are written in new ENDF formatted file.;

The requirements to the task input file are presented in the file LINEAR_TAB.pdf.

LINEAR_TAB.pdf

Line	Column (format)	Explanation of parameters
1	1-11 (І11)	Selection criteria (0=MAT, 1=ZA) (DEFault = 0)
	12-22 (І11)	Monitor mode selector: = 0 – normal operation (DEF) = 1 – monitor progress of linearizing of the data (this option may be used in order to monitor the execution speed of long running jobs)
	23-33 (E11.4)	Minimum cross section of interest (barns) 0.0 or less - the program will use 1.0e-10 barn (DEF). nergy intervals will not be sub-divided if the absolute value of the cross section within the interval is less than this value. An exception to this rule is near thresholds energy intervals will be sub-divided until convergence regardless of the magnitude of the cross section.
	34-44 (І11)	Keep original evaluated data points = 0 – no (DEF) = 1 – yes
2	1-60 (А60)	ENDF/B input data filename (DEF option ENDFB.IN)
3	1-60 (А60)	ENDF/B output data filename (DEF option ENDFB.OUT)
4-N	1 - 6 (І6)	Lower MAT or ZA limit	Up to 100 ranges may be specified, only one range per line. If the upper MAT/ZA limit of any request is less than the low limit it will be set equal to the lower limit. If the upper MAT limit is still zero it will be set equal to 9999. If the upper MF or MT limit is zero it will be set to 99 or 999 respectively. The list of ranges is terminated by a blank line.
	7 - 8 (І2)	Lower MF
	9-11 (І3)	Lower MT
	12-17 (І6)	Upper MAT or ZA limit
	18-19 (І2)	Upper MF
	20-22 (І3)	Upper MT
К	1-11 (E11.4)	Energy for error law	If the error law is energy independent only a single error is given (DEF 0.001) If the error law is energy dependent up to 20 energy, error pairs are allowed. For an energy dependent error law all energies must be ascending energy order. The end of error law is terminated by a blank line.
	12-22 (E11.4)	Allowable fractional error for error law

        To facilitate the work with LINEAR we present a version of the task input file LINEAR.inp (several examples of task input file anybody find in the end of file LINEAR.pdf).

Let tape-1 is the ENDF formatted file, which contains several materials. Assuming that we intend to linearize within an accuracy of 1 per-cent (0.01 as a fraction) all neutron cross sections for materials, included in tape-1. Let name of output ENDF formatted file will be RESULT.1. The asterisks in this example, following below, in input file have to correspond to the blanks. Here they are presented to facilitate the calculation of positions. ********10********20********30********40********50********60********70********80 12345678901234567890123456789012345678901234567890123456789012345678901234567890 **********0**********0*0.1000E-09**********0 tape-1 RESULT.1 *****1*1**1**999999999 ******************************************************************************** ************0.1000E-01 ******************************************************************************** 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Running of the code: LINEAR.EXE.