Radiance dctimestep program

DCTIMESTEP(1)                                                    DCTIMESTEP(1)

NAME

       dctimestep - compute annual simulation time-step via matrix multiplica-
       tion

SYNOPSIS

       dctimestep Vspec Tbsdf.xml Dmat.dat [ tregvec ]

DESCRIPTION

       Dctimestep takes four input files, forming a  matrix  expression.   The
       first argument is the View matrix file that specifies how window output
       directions are related to some set of measured values, such as an array
       of  illuminance  points  or images.  This matrix is usually computed by
       rtcontrib(1) for a particular set of windows or skylight openings.  The
       second  argument is the window transmission matrix, or BSDF, given as a
       standard XML description.  The third argument is  the  Daylight  matrix
       file  that  defines  how  sky patches relate to input directions on the
       same opening.  This  is  usually  computed  using  genklemsamp(1)  with
       rtcontrib  in  a  separate run for each window or skylight orientation.
       The final input is the sky contribution  vector,  usually  computed  by
       genskyvec(1),  which  may  be  passed on the standard input.  This data
       must be in ASCII format, whereas the View  and  Daylight  matrices  are
       more efficiently represented as binary float data if machine byte-order
       is not an issue.

       Sent to the standard output of dctimestep is either an ASCII color vec-
       tor  with as many RGB triplets as there are rows in the View matrix, or
       a combined Radiance picture.  Which output is produced depends  on  the
       Vspec  argument.  A regular file name will be loaded and interpreted as
       a matrix to generate a color results vector.  A file specification con-
       taining  a '%d' format string will be interpreted as a list of Radiance
       component pictures, which will be summed according to the computed vec-
       tor.

EXAMPLES

       To  compute a set of illuminance contributions for Window 1 on the Win-
       ter solstice at 2pm:

         gensky 12 21 14 | genskyvec | dctimestep IllPts.vmx Blinds20.xml Win-
         dow1.dmx > Ill_12-21-14.dat

       To compute Window2's contribution to an interior view at 12 noon on the
       Summer solstice:

         gensky 6 21 12 | genskyvec  |  dctimestep  view%03d.hdr  Blinds30.xml
         Window2.dmx > view_6-21-12.hdr

AUTHOR

       Greg Ward

SEE ALSO

       genklemsamp(1),   genskyvec(1),  mkillum(1),  rtcontrib(1),  rtrace(1),
       vwrays(1)

RADIANCE                           12/09/09                      DCTIMESTEP(1)