Changes in version 1.5 (October, 10th, 2001)

• Modified components
• A corrected version of Arm.comp. For further information, see the emails by Ulrich Wildgruber and Stuart Rycroft. (Apr. 26, 2001)
• A corrected version of  Monitor_nD.comp. For further information, see the email by Emmanuel Farhi. (Apr. 26, 2001)
• A rewritten version of Gravity_guide.comp has been contributed by Emmanuel Farhi (see email). The component provided in the email works with McStas 1.4.2, but the official version of the component is not working with McStas 1.4.2 because support for this component has been added to the kernel. (Aug. 7, 2001)
• An updated version of Monitor_nD.comp has been contributed by Emmanuel Farhi (see first and second email). The new version of the component is not working with McStas 1.4.2 because support for the component has been added to the kernel. (Aug. 8, 2001)
• Andrew Wildes and Emmanuel Farhi have detected an error when using focusing geometry in Channeled_guide. The slope of the channels is not computed corrected correctly, because the same left and right slopes are used in all channels. This has now been included properly in Gravity_guide, and it is recommended that this component is used. (Sep. 18, 2001)
• The handling of illumination in Source_flat, Source_div and Source_flat_lambda have been corrected. (Oct. 9, 2001)
• New components
• The He3_cell.comp has been contributed by Trefor Roberts. It models a cylindrical ³He spin filter cell. (Aug. 8, 2001)
• The Mon_2foc.comp has been contributed by Peter Link. It models a double bent monochromator with multiple slabs. (Aug. 9, 2001)
• The Bender.comp has been contributed by Philipp Bernhardt. It models a curved neutron guide. (Aug. 10, 2001)
• The Powder_filter.comp has been contributed by Ben Fortescue. It models a general box-shaped powder filter. (Aug. 16, 2001)
• The Source_Maxwell_3 component describes a source with three Maxwellian distributions. (Sep. 17, 2001)
• Various monitors have been added: EPSD_monitor, PSDcyl_monitor, PSDlin_monitor, TOF_cylPSD_monitor, TOFlog_mon. (Sep. 18, 2001)
• A minor error in TOF_cylPSD_monitor has been corrected. (Oct. 9, 2001)
• A new monitor TOFLambda_monitor has been added. (Oct. 9, 2001)
• A guide modeling waviness, Guide_wavy, has been added. (Oct. 9, 2001)
• A generic source, Source_gen, has been added. (Oct. 10, 2001)
• The signal handling system has been updated to handle a special case. The signal handling system will be documented in the manual of version 1.5. (Aug. 7, 2001)
• The representation of polarisation in McStas components and instruments is supposed to work as follows. Only components actually modifying the spin explicitly require the "POLARISATION PARAMETERS (sx,sy,sz)" line. An instrument handling polarisation may consist of  components both with and without this line; it will transform the spin vector correctly anyway. The  "POLARISATION PARAMETERS (sx,sy,sz)" line is therefore removed from all official components not dealing with polarisation. The reason is that for instruments without polarisation some simulation time is gained by excluding the transformations of the spin vector. (Aug. 9, 2001)
• Some definitions have been added that can be used in coding components:
• NAME_CURRENT_COMP gives the name of the current component as a string. (Aug. 16, 2001)
• POS_A_CURRENT_COMP gives the absolute position of the current component. A component of the vector is referred to as POS_A_CURRENT_COMP.i where i is x, y or z. (Aug. 16, 2001)
• ROT_A_CURRENT_COMP and  ROT_R_CURRENT_COMP give the orientation of the current component as rotation matrices (absolute orientation and the orientation relative to the previous component, respectively). A component of  a rotation matrice is referred to as  ROT_A_CURRENT_COMP[m][n], where m and n are 0, 1, or 2. (Aug. 16, 2001)
• POS_A_COMP(comp) gives the absolute position of the component with the name comp. Note that comp is not given as a string. A component of the vector is referred to as POS_A_COMP(comp).i where i is x, y or z. (Aug. 16, 2001)
• ROT_A_COMP(comp) and ROT_R_COMP(comp)  give the orientation of the component comp as rotation matrices (absolute orientation and the orientation relative to its previous component, respectively). Note that comp is not given as a string. A component of  a rotation matrice is referred to as  ROT_A_COMP(comp)[m][n], where m and n are 0, 1, or 2. (Aug. 16, 2001)

Extensions and updates included in version 1.4.2

• A three-component representation of the spin is supported and the polarisation state vector has been added to all components available in the McStas release (which is not equivalent to the McDoc webpage). However, no components actually using polarisation are available in this version. For users writing components, an additional line "POLARISATION PARAMETERS (sx,sy,sz)" has to be added to the component preferrably after the "STATE PARAMETERS" line. Full documentation will be given in version 1.5.  (Apr. 6, 2001)
• See note above from Aug. 9, 2001
• An updated version of Monitor_nD.comp has been provided by Emmanuel Farhi. (Apr. 5, 2001)

Extensions and updates included in version 1.4.1

• An updated version of Monitor_nD.comp  has been provided by Emmanuel Farhi. Support for monitoring correlations has been included that requires the new component PreMonitor_nD.comp. For further information, see the email by Emmanuel. (Feb. 19, 2001)
• Corrected versions of Monitor_nD.comp, Monitor_Optimizer.comp and Source_Optimizer.comp have been provided by Emmanuel Farhi (they have been available at the ILL page for a while). (Feb. 19, 2001)
• Generic long- and short-pulse components, ESS_moderator_long.comp and ESS_moderator_short.comp, have been developed by Kim Lefmann. The components cover all target station/moderator combinations currently discussed by the ESS Instrumentation Group. (Feb. 23, 2001)
• The declaration of the counter of simulation steps run_num has been changed from int to double. This should (at least partly) solve the problem regarding that the maximum number of simulation steps is limited by the maximum number that can be used for an int in C. (Mar. 13, 2001)
• A signal handler has been provided by Emmanuel Farhi. For further information, see the email by Emmanuel. Consequently, the name of the variable run_num discussed in the previous entry has been changed to mcrun_num. (Mar. 13, 2001)
• A new component Source_Maxwell.comp and updated versions of Monitor_nD.comp, PreMonitor_nD.comp, and Source_Optimizer.comp have been provided by Emmanuel Farhi. (Mar. 14, 2001)
• The update required for correctly handling string parameters in instruments pointed out by Emmanuel Farhi is included. For further information, see the email by Emmanuel. (Mar. 14, 2001)
• An updated version of Gravity_guide.comp has been provided by Kim Lefmann correcting the errors concerning the protection of variables. Gravity_guide.comp has previously been an unofficial component, but is now included in the official version. (Mar. 15, 2001)
• The maximum number of lines in a component has been changed to 5000 by modifying MAX_ELEMENTS in list.c, which of course only partly solves the problem. (Mar. 15, 2001)