man/man1/gendaymtx.1

.\" RCSid $Id: gendaymtx.1,v 1.3 2013/02/05 19:31:40 greg Exp $
.TH GENDAYMTX 1 01/19/13 RADIANCE
.SH NAME
gendaymtx - generate an annual Perez sky matrix from a weather tape
.SH SYNOPSIS
.B gendaymtx
[
.B "\-v"
][
.B "\-d|\-s"
][
.B "\-r deg"
][
.B "\-m N"
][
.B "\-g r g b"
][
.B "\-c r g b"
][
.B "-o{f|d}"
][
.B "-O{0|1}"
]
[
.B "tape.wea"
]
.SH DESCRIPTION
.I Gendaymtx
takes a weather tape as input and produces a matrix of sky patch
values using the Perez all-weather model.
The weather tape is assumed to be in the simple ASCII format understood
by DAYSIM, which contains a short header with the site parameters followed
by the month, day, standard time, direct normal and diffuse horizontal
irradiance values, one time step per line.
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
Increasing the
.I \-m
parameter, typically by factors of two, 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 three values, corresponding to
red green and blue radiance channels (watts/sr/meter^2).
Thus, an hourly weather tape for an entire year would
yield 8760x3 (26280) values per output line (row).
.PP
The
.I \-c
option may be used to specify a color for the sky.
The gray value should equal 1 for proper energy balance
The default sky color is
.I "\-c 0.960 1.004 1.118".
Similarly, the
.I \-g
option may be used to specify a ground color.
The default value is
.I "\-g 0.2 0.2 0.2"
corresponding to a 20% gray.
.PP
The
.I \-d
option may be used to produce a sun-only matrix, with no sky contributions.
Alternatively, the
.I \-s
option may be used to exclude any direct solar component from the output.
.PP
By default,
.I gendaymtx
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 \-O1
option specifies that output should be total solar radiance rather
than visible radiance.
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 uncolored Tregenza sky matrix without solar direct:
.IP "" .2i
gendaymtx -m 1 -c 1 1 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
gendaymtx -m 4 -of VancouverBC.wea | dctimestep -if -n 8760 DCoef.mtx > res.dat
.SH AUTHORS
Ian Ashdown wrote most of the code,
based on Jean-Jacques Delaunay's original gendaylit(1) implementation.
Greg Ward wrote the final parameter parsing and weather tape conversion.
.SH "SEE ALSO"
dctimestep(1), genBSDF(1), gendaylit(1), gensky(1), genskyvec(1), rcontrib(1),
xform(1)
Revision:	1.4
Committed:	Tue Apr 30 17:05:27 2013 UTC (12 years ago) by greg
Branch:	MAIN
Changes since 1.3:	+7 -1 lines
Log Message:	Added -O1 option to output total solar radiance
#	Content
1	.\" RCSid $Id: gendaymtx.1,v 1.3 2013/02/05 19:31:40 greg Exp $
2	.TH GENDAYMTX 1 01/19/13 RADIANCE
3	.SH NAME
4	gendaymtx - generate an annual Perez sky matrix from a weather tape
5	.SH SYNOPSIS
6	.B gendaymtx
7	[
8	.B "\-v"
9	][
10	.B "\-d\|\-s"
11	][
12	.B "\-r deg"
13	][
14	.B "\-m N"
15	][
16	.B "\-g r g b"
17	][
18	.B "\-c r g b"
19	][
20	.B "-o{f\|d}"
21	][
22	.B "-O{0\|1}"
23	]
24	[
25	.B "tape.wea"
26	]
27	.SH DESCRIPTION
28	.I Gendaymtx
29	takes a weather tape as input and produces a matrix of sky patch
30	values using the Perez all-weather model.
31	The weather tape is assumed to be in the simple ASCII format understood
32	by DAYSIM, which contains a short header with the site parameters followed
33	by the month, day, standard time, direct normal and diffuse horizontal
34	irradiance values, one time step per line.
35	Each time step line is used to compute a column in the output matrix,
36	where rows correspond to sky patch positions, starting with 0 for
37	the ground and continuing to 145 for the zenith using the default
38	.I "\-m 1"
39	parameter setting.
40	.PP
41	Increasing the
42	.I \-m
43	parameter, typically by factors of two, yields a higher resolution
44	sky using the Reinhart patch subdivision.
45	For example, setting
46	.I "\-m 4"
47	yields a sky with 2305 patches plus one patch for the ground.
48	Each matrix entry is in fact three values, corresponding to
49	red green and blue radiance channels (watts/sr/meter^2).
50	Thus, an hourly weather tape for an entire year would
51	yield 8760x3 (26280) values per output line (row).
52	.PP
53	The
54	.I \-c
55	option may be used to specify a color for the sky.
56	The gray value should equal 1 for proper energy balance
57	The default sky color is
58	.I "\-c 0.960 1.004 1.118".
59	Similarly, the
60	.I \-g
61	option may be used to specify a ground color.
62	The default value is
63	.I "\-g 0.2 0.2 0.2"
64	corresponding to a 20% gray.
65	.PP
66	The
67	.I \-d
68	option may be used to produce a sun-only matrix, with no sky contributions.
69	Alternatively, the
70	.I \-s
71	option may be used to exclude any direct solar component from the output.
72	.PP
73	By default,
74	.I gendaymtx
75	assumes the positive Y-axis points north such that the first sky patch
76	is in the Y-axis direction on the horizon, the second patch is just
77	west of that, and so on spiraling around to the final patch near the zenith.
78	The
79	.I \-r
80	(or
81	.I \-rz)
82	option rotates the sky the specified number of degrees counter-clockwise
83	about the zenith, i.e., west of north.
84	This is in keeping with the effect of passing the output of
85	.I gensky(1)
86	or
87	.I gendaylit(1)
88	through
89	.I xform(1)
90	using a similar transform.
91	.PP
92	The
93	.I \-of
94	or
95	.I \-od
96	option may be used to specify binary float or double output, respectively.
97	This is much faster to write and to read, and is therefore preferred on
98	systems that support it.
99	(MS Windows is not one of them.)\0
100	The
101	.I \-O1
102	option specifies that output should be total solar radiance rather
103	than visible radiance.
104	Finally, the
105	.I \-v
106	option will enable verbose reporting, which is mostly useful for
107	finding out how many time steps are actually in the weather tape.
108	.SH EXAMPLES
109	Produce an uncolored Tregenza sky matrix without solar direct:
110	.IP "" .2i
111	gendaymtx -m 1 -c 1 1 1 -s Detroit.wea > Detroit.mtx
112	.PP
113	Produce an hourly, annual Reinhart sky matrix
114	with 2306 patches including solar contributions
115	and send float output to
116	.I dctimestep(1)
117	to compute a sensor value matrix:
118	.IP "" .2i
119	gendaymtx -m 4 -of VancouverBC.wea \| dctimestep -if -n 8760 DCoef.mtx > res.dat
120	.SH AUTHORS
121	Ian Ashdown wrote most of the code,
122	based on Jean-Jacques Delaunay's original gendaylit(1) implementation.
123	Greg Ward wrote the final parameter parsing and weather tape conversion.
124	.SH "SEE ALSO"
125	dctimestep(1), genBSDF(1), gendaylit(1), gensky(1), genskyvec(1), rcontrib(1),
126	xform(1)