man/man1/gensdaymtx.1

.\" RCSid $Id: gensdaymtx.1,v 1.1 2024/08/02 19:10:18 greg Exp $
.TH GENSDAYMTX 1 01/19/13 RADIANCE
.SH NAME
gensdaymtx - generate an annual spectral sky matrix from a weather tape
.SH SYNOPSIS
.B gensdaymtx
[
.B "\-v"
][
.B "\-h"
][
.B "\-d|\-s"
][
.B "\-u"
]][
.B "\-r deg"
][
.B "\-m N"
][
.B "\-p Dir"
][
.B "\-n N"
][
.B "-o{f|d}"
]
[
.B "tape.wea"
]
.SH DESCRIPTION
.I Gensdaymtx
takes a weather tape as input and produces a matrix of spectral sky patch
values using the precomputed atmospheric scattering model.
Unlike the similarly-named
.I gendaymtx
tool, the Perez sky model is not used.
The weather tape is assumed to be in a special form of the .wea file, which contains 
a short header with the site parameters followed
by the month, day, standard time, direct normal and diffuse horizontal
irradiance values, total cloud cover, and broadband aerosol optical depth, one time step per line.
Such file can be generated by 
.I epw2wea 
with the
.I \-a 
flag.
Each time step line is used to compute a column in the output matrix,
where rows correspond to sky patch positions, starting with 0 for
the ground and continuing to 145 for the zenith using the default
.I "\-m 1"
parameter setting.
.PP
.I Gensdaymtx
uses the OPAC continental average aerosol profile for the Mie scattering calculation. 
For every distinct AOD value in the weather tape, a new set of the atmospheric parameters 
is computed and stored in the atmos_data directory in the current directory, which 
can be changed using the -p flag. This precomputation can be sped up using the
.I \-n NThreads
option. There is no speedup after NTHREADS=16.
.PP
Increasing the
.I \-m
parameter yields a higher resolution
sky using the Reinhart patch subdivision.
For example, setting
.I "\-m 4"
yields a sky with 2305 patches plus one patch for the ground.
Each matrix entry is in fact 20 values, corresponding to
spectra from 380nm to 730nm at 20nm interval (watts/sr/meter^2).
Thus, an hourly weather tape for an entire year would
yield 8760x20 (175200) values per output line (row).
.PP
The
.I \-g
option may be used to specify a ground color.
The default value is
.I "\-g 0.2"
corresponding to a 20% gray.
.PP
If there is a sun in the description,
.I gensdaymtx
will include its contribution in the four nearest sky patches,
distributing energy according to centroid proximity.
The
.I \-d
option may be used to produce a sun-only matrix, with no sky contributions,
and the ground patch also set to zero.
Alternatively, the
.I \-s
option may be used to exclude any direct solar component from the output,
with the other sky and ground patches unaffected.
.PP
The
.I \-u
option ignores input times when the sun is below the horizon.
.PP
By default,
.I gensdaymtx
assumes the positive Y-axis points north such that the first sky patch
is in the Y-axis direction on the horizon, the second patch is just
west of that, and so on spiraling around to the final patch near the zenith.
The
.I \-r
(or
.I \-rz)
option rotates the sky the specified number of degrees counter-clockwise
about the zenith, i.e., west of north.
This is in keeping with the effect of passing the output of
.I gensky(1)
or
.I gendaylit(1)
through
.I xform(1)
using a similar transform.
.PP
The
.I \-of
or
.I \-od
option may be used to specify binary float or double output, respectively.
This is much faster to write and to read, and is therefore preferred on
systems that support it.
(MS Windows is not one of them.)\0
The
.I \-h
option prevents the output of the usual header information.
Finally, the
.I \-v
option will enable verbose reporting, which is mostly useful for
finding out how many time steps are actually in the weather tape.
.SH EXAMPLES
Produce an annual spectral sky matrix without solar direct:
.IP "" .2i
epw2wea Detroit.epw Detroit.wea -a; 
gensdaymtx -m 1 -s Detroit.wea > Detroit.mtx
.PP
Produce an hourly, annual Reinhart sky matrix
with 2306 patches including solar contributions
and send float output to
.I dctimestep(1)
to compute a sensor value matrix:
.IP "" .2i
gensdaymtx -m 4 -of VancouverBC.wea | dctimestep -if -n 8760 DCoef.mtx > res.dat
.SH AUTHORS
Taoning Wang
.SH "SEE ALSO"
dctimestep(1), epw2wea(1),
genBSDF(1), gendaylit(1), gendaymtx(1), gensky(1), genskyvec(1), genssky(1),
rcollate(1), rcomb(1), rcontrib(1), rfluxmtx(1), rmtxop(1), xform(1)
Revision:	1.2
Committed:	Mon Aug 5 17:23:56 2024 UTC (8 months, 4 weeks ago) by greg
Branch:	MAIN
Changes since 1.1:	+9 -5 lines
Log Message:	docs: Slight wording modifications and added links to other tools
#	User	Rev	Content
1	greg	1.2	.\" RCSid $Id: gensdaymtx.1,v 1.1 2024/08/02 19:10:18 greg Exp $
2	greg	1.1	.TH GENSDAYMTX 1 01/19/13 RADIANCE
3			.SH NAME
4			gensdaymtx - generate an annual spectral sky matrix from a weather tape
5			.SH SYNOPSIS
6			.B gensdaymtx
7			[
8			.B "\-v"
9			][
10			.B "\-h"
11			][
12			.B "\-d\|\-s"
13			][
14			.B "\-u"
15			]][
16			.B "\-r deg"
17			][
18			.B "\-m N"
19			][
20			.B "\-p Dir"
21			][
22			.B "\-n N"
23			][
24			.B "-o{f\|d}"
25			]
26			[
27			.B "tape.wea"
28			]
29			.SH DESCRIPTION
30			.I Gensdaymtx
31			takes a weather tape as input and produces a matrix of spectral sky patch
32			values using the precomputed atmospheric scattering model.
33	greg	1.2	Unlike the similarly-named
34			.I gendaymtx
35			tool, the Perez sky model is not used.
36	greg	1.1	The weather tape is assumed to be in a special form of the .wea file, which contains
37			a short header with the site parameters followed
38			by the month, day, standard time, direct normal and diffuse horizontal
39			irradiance values, total cloud cover, and broadband aerosol optical depth, one time step per line.
40			Such file can be generated by
41			.I epw2wea
42	greg	1.2	with the
43	greg	1.1	.I \-a
44			flag.
45			Each time step line is used to compute a column in the output matrix,
46			where rows correspond to sky patch positions, starting with 0 for
47			the ground and continuing to 145 for the zenith using the default
48			.I "\-m 1"
49			parameter setting.
50			.PP
51			.I Gensdaymtx
52			uses the OPAC continental average aerosol profile for the Mie scattering calculation.
53			For every distinct AOD value in the weather tape, a new set of the atmospheric parameters
54			is computed and stored in the atmos_data directory in the current directory, which
55			can be changed using the -p flag. This precomputation can be sped up using the
56			.I \-n NThreads
57			option. There is no speedup after NTHREADS=16.
58			.PP
59			Increasing the
60			.I \-m
61			parameter yields a higher resolution
62			sky using the Reinhart patch subdivision.
63			For example, setting
64			.I "\-m 4"
65			yields a sky with 2305 patches plus one patch for the ground.
66			Each matrix entry is in fact 20 values, corresponding to
67			spectra from 380nm to 730nm at 20nm interval (watts/sr/meter^2).
68			Thus, an hourly weather tape for an entire year would
69			yield 8760x20 (175200) values per output line (row).
70			.PP
71			The
72			.I \-g
73			option may be used to specify a ground color.
74			The default value is
75			.I "\-g 0.2"
76			corresponding to a 20% gray.
77			.PP
78			If there is a sun in the description,
79			.I gensdaymtx
80			will include its contribution in the four nearest sky patches,
81			distributing energy according to centroid proximity.
82			The
83			.I \-d
84			option may be used to produce a sun-only matrix, with no sky contributions,
85			and the ground patch also set to zero.
86			Alternatively, the
87			.I \-s
88			option may be used to exclude any direct solar component from the output,
89			with the other sky and ground patches unaffected.
90			.PP
91			The
92			.I \-u
93			option ignores input times when the sun is below the horizon.
94			.PP
95			By default,
96			.I gensdaymtx
97			assumes the positive Y-axis points north such that the first sky patch
98			is in the Y-axis direction on the horizon, the second patch is just
99			west of that, and so on spiraling around to the final patch near the zenith.
100			The
101			.I \-r
102			(or
103			.I \-rz)
104			option rotates the sky the specified number of degrees counter-clockwise
105			about the zenith, i.e., west of north.
106			This is in keeping with the effect of passing the output of
107			.I gensky(1)
108			or
109			.I gendaylit(1)
110			through
111			.I xform(1)
112			using a similar transform.
113			.PP
114			The
115			.I \-of
116			or
117			.I \-od
118			option may be used to specify binary float or double output, respectively.
119			This is much faster to write and to read, and is therefore preferred on
120			systems that support it.
121			(MS Windows is not one of them.)\0
122			The
123			.I \-h
124			option prevents the output of the usual header information.
125			Finally, the
126			.I \-v
127			option will enable verbose reporting, which is mostly useful for
128			finding out how many time steps are actually in the weather tape.
129			.SH EXAMPLES
130			Produce an annual spectral sky matrix without solar direct:
131			.IP "" .2i
132			epw2wea Detroit.epw Detroit.wea -a;
133			gensdaymtx -m 1 -s Detroit.wea > Detroit.mtx
134			.PP
135			Produce an hourly, annual Reinhart sky matrix
136			with 2306 patches including solar contributions
137			and send float output to
138			.I dctimestep(1)
139			to compute a sensor value matrix:
140			.IP "" .2i
141			gensdaymtx -m 4 -of VancouverBC.wea \| dctimestep -if -n 8760 DCoef.mtx > res.dat
142			.SH AUTHORS
143	greg	1.2	Taoning Wang
144	greg	1.1	.SH "SEE ALSO"
145	greg	1.2	dctimestep(1), epw2wea(1),
146			genBSDF(1), gendaylit(1), gendaymtx(1), gensky(1), genskyvec(1), genssky(1),
147			rcollate(1), rcomb(1), rcontrib(1), rfluxmtx(1), rmtxop(1), xform(1)