ViewVC Help
View File | Revision Log | Show Annotations | Download File | Root Listing
root/radiance/ray/doc/man/man1/dctimestep.1
Revision: 1.8
Committed: Sat Feb 8 01:28:05 2014 UTC (11 years, 3 months ago) by greg
Branch: MAIN
Changes since 1.7: +30 -3 lines
Log Message:
Added -od and -of options for binary output

File Contents

# Content
1 .\" RCSid $Id: dctimestep.1,v 1.7 2013/09/05 17:53:22 greg Exp $"
2 .TH DCTIMESTEP 1 12/09/09 RADIANCE
3 .SH NAME
4 dctimestep - compute annual simulation time-step(s) via matrix multiplication
5 .SH SYNOPSIS
6 .B dctimestep
7 [
8 .B "\-n nsteps"
9 ][
10 .B "\-o ospec"
11 ][
12 .B "\-i{f|d}
13 ][
14 .B "\-o{f|d}
15 ]
16 .B DCspec
17 [
18 .B skyf
19 ]
20 .br
21 .B dctimestep
22 [
23 .B "\-n nsteps"
24 ][
25 .B "\-o ospec"
26 ][
27 .B "\-i{f|d}
28 ][
29 .B "\-o{f|d}
30 ]
31 .B Vspec
32 .B Tbsdf.xml
33 .B Dmat.dat
34 [
35 .B skyf
36 ]
37 .SH DESCRIPTION
38 .I Dctimestep
39 has two invocation forms.
40 In the first form,
41 .I dctimestep
42 is given a daylight coefficient specification and an optional sky
43 vector or matrix, which may be read from the standard input if unspecified.
44 The daylight coefficients are multiplied against these sky values
45 and the results are written to the standard output.
46 This may be a list of color values or a combined Radiance image,
47 as explained below.
48 .PP
49 In the second form,
50 .I dctimestep
51 takes four input files, forming a matrix expression.
52 The first argument is the View matrix file that specifies how window output
53 directions are related to some set of measured values, such as an array of
54 illuminance points or images.
55 This matrix is usually computed by
56 .I rcontrib(1)
57 for a particular set of windows or skylight openings.
58 The second argument is the window transmission matrix, or BSDF, given as
59 a standard XML description.
60 The third argument is the Daylight matrix file that defines how sky patches
61 relate to input directions on the same opening.
62 This is usually computed using
63 .I genklemsamp(1)
64 with
65 .I rcontrib
66 in a separate run for each window or skylight orientation.
67 The last file is the sky contribution vector or matrix,
68 typically computed by
69 .I genskyvec(1)
70 or
71 .I gendaymtx(1),
72 and may be passed on the standard input.
73 This data is assumed by default to be in ASCII format, whereas the
74 formats of the View and Daylight matrices
75 are detected automatically if given as binary data.
76 The
77 .I \-if
78 or
79 .I \-id
80 option may be used to specify that sky data is in float or double
81 format, respectively, which is more efficient for large matrices.
82 (Note that binary double data may not be read from stdin.)\0
83 .PP
84 Sent to the standard output of
85 .I dctimestep
86 is either a color vector with as many RGB triplets
87 as there are rows in the View matrix, or a combined
88 .I Radiance
89 picture.
90 Which output is produced depends on the first argument.
91 A regular file name will be loaded and interpreted as a matrix to
92 generate a color results vector.
93 A file specification containing a '%d' format string will be
94 interpreted as a list of
95 .I Radiance
96 component pictures, which will be summed according to the computed
97 vector.
98 .PP
99 The
100 .I \-n
101 option may be used to compute multiple time steps in a
102 single invocation.
103 The sky input file must contain the number of
104 columns specified in each sky patch row, whether it is read
105 from the standard input or from a file.
106 The columns do not need to be given on the same
107 line, so long as the number of values totals 3*Nsteps*Npatches.
108 Input starts from the first patch at the first time step, then the
109 first patch at the second time step, and so on.
110 .PP
111 The
112 .I \-o
113 option may be used to specify a file or a set of output files
114 to use rather than the standard output.
115 If the given specification contains a '%d' format string, this
116 will be replaced by the time step index, starting from 1.
117 In this way, multiple output pictures may be produced,
118 or separate result vectors (one per time step).
119 If the standard output is used or the
120 .I \-o
121 option specifies a single output file, then an information header
122 will precede the output.
123 This can be removed if desired using the
124 .I getinfo\(1\)
125 command with a single hyphen ('-') argument.
126 .PP
127 The
128 .I \-of
129 or
130 .I \-od
131 option may be used to specify IEEE float or double binary output
132 data, respectively.
133 This enables
134 .I dctimestep
135 to be used as a pure matrix multiplier, as the output file with
136 header specifying the format is suitable for subsequent calls.
137 .SH EXAMPLES
138 To compute workplane illuminances at 3:30pm on Feb 10th:
139 .IP "" .2i
140 gensky 2 10 15:30 | genskyvec | dctimestep workplaneDC.dmx > Ill_02-10-1530.dat
141 .PP
142 To compute an image at 10am on the equinox from a set of component images:
143 .IP "" .2i
144 gensky 3 21 10 | genskyvec | dctimestep dcomp%03d.hdr > view_03-21-10.hdr
145 .PP
146 To compute a set of illuminance contributions for Window 1 on
147 the Winter solstice at 2pm:
148 .IP "" .2i
149 gensky 12 21 14 | genskyvec | dctimestep IllPts.vmx Blinds20.xml Window1.dmx > Ill_12-21-14.dat
150 .PP
151 To compute Window2's contribution to an interior view at 12 noon on the Summer solstice:
152 .IP "" .2i
153 gensky 6 21 12 | genskyvec | dctimestep view%03d.hdr Blinds30.xml
154 Window2.dmx > view_6-21-12.hdr
155 .PP
156 To generate an hourly matrix of sensor value contributions from Skylight3
157 using a 3-phase calculation, where output columns are time steps:
158 .IP "" .2i
159 gendaymtx -of Tampa.wea | dctimestep -if -n 8760 WPpts.vmx
160 shade3.xml Skylight3.dmx > wp_win3.dat
161 .IP "" .2i
162 .PP
163 Generate a series of pictures corresponding to timesteps
164 in an annual simulation:
165 .IP "" .2i
166 gendaymtx NYCity.wea | dctimestep -n 8760 -o tstep%04d.hdr dcomp%03d.hdr
167 .PP
168 To multiply two color matrices (second matrix is IEEE-float with
169 145 RGB columns) into a IEEE-double result (also 145 RGB columns):
170 .IP "" .2i
171 getinfo - < Inp2.fmx | dctimestep -n 145 -if -od Inp1.fmx > Inp1xInp2.dmx
172 .SH AUTHOR
173 Greg Ward
174 .SH "SEE ALSO"
175 gendaymtx(1), genklemsamp(1), genskyvec(1), getinfo(1),
176 mkillum(1), rcollate(1), rcontrib(1), rtrace(1), vwrays(1)