smigen

This HDF file contains:

1. a byte-valued or int16-valued HDF SD in global Equidistant Cylindrical projection
2. global file attributes
3. a color palette

Byte and int16 SD values can be converted back to geophysical values by using the global attributes Scaling, Scaling Equation, Base, Slope and Intercept, where Scaling Equation will be one of:

• Linear scaling:  Geophysical value  =  (Slope*l3m_data) + Intercept
• Logarithmic scaling:  Geophysical value  =  Base**((Slope*l3m_data) + Intercept)

The SMI default data value format is 8-bit integer, lacking the full precision of the original retrieval. Also, the SMI format presents the data in an equirectangilar grid, which means the spatial resolution varies with latitude. In contrast, the binned products maintain the data in an equal-area projection. Generally speaking, it is recommended that you use the binned products when doing detailed, quantitative analysis, and you use the SMI products when you just want easy access to a global image.

[Command Mode][Interactive Mode]

Command Mode:

Usage:  smigen, ifile="ifile", prod_name="prod_name", projection=projection, resolution=resolution, precision=precision, latnorth=latnorth, latsouth=latsouth, lonwest=lonwest, loneast=loneast, stat=stat, stype=stype, range=range, palette=palette, ofile=ofile, nosubmit=nosubmit, help=help

Minimum command:  smigen, ifile="ifile", prod_name="prod_name"

Examples:  Note that to specify multiple products, you may either run smigen several times in succession, or specify several products at once. If you specify several products at once, and wish to override the product defaults, all arguments will accept arrays of values (see example 2 below).

   (1) smigen, ifile="l3b.hdf", prod_name="chlor_a",stype='lin'

   (2) smigen, ifile="l3b.hdf", prod_name=["chlor_a","sst"],precision=["B","I"]

Arguments/Keywords:

ifile	Input Level-3 binned HDF file. (Required)
prod_name	Geo-Physical product name(s). See the list below. (Required)
projection	Output projection type.  SIN or RECT (Default='RECT').
resolution	Output resolution.  SMI, SMI4, LAND, 36km, 9km, 4km, 2km, or 1km.   (Default='9km')
precision	Output datatype.  B=Byte (8-bit int), I=Integer (16-bit int).  (Default=B)
latnorth	Northernmost latitude used for output.  (Default=90.0)
latsouth	Southernmost latitude used for output.  (Default=-90.0)
lonwest	Westernmost longitude used for output.  (Default=-180.0)
loneast	Easternmost longitude used for output.  (Default=180.0)
stat	Measure to calculate.  The following variables are stored for every bin in the L3-binned input file and are used in calculating the measures: s = sums of all values input to the bin ssq = sums of the squares of all input values to the bin wt = weight assigned to that bin ns = number of scenes input to that bin stat value Measure calculated Defined at a given bin as: 1 Mean(Default) s/wt 2 Variance tmp_var = (ssq/wt)-(mean**2) var = (tmp_var * wt**2) / ((wt**2)-ns) 3 Standard Deviation sqrt(var) 4 Pixels number of Level-2 input values that went into creating the Level-3 bin selected for each grid point 5 Scenes number of Level-2 input files that went into creating the Level-3 bin selected for each grid point
stype	Scaling type to use: 'lin'=Linear, 'log'=Log. (See defaults below).
range	Data range for scaling : [dmin, dmax]. (See defaults below).
palette	Name of ASCII color palette. (Default is the SMI chlor or sst color palette).
ofile	Output file name. (Default is to automatically generate output file name.)
help	Print command usage to screen.
nosubmit	Do not submit commands, just print them.

Product Names and Scaling Defaults
(Note that minimum data values correspond to byte=0, int16=0 and maximum data values correspond to byte=250, int16=65534.)

Product	Data min	Data max	Slope for BYTE	Slope for INT16	Intercept	Scaling
nLw_412	0.0	5.08	0.02032	7.75170e-5	0.0	Linear
nLw_443	0.0	3.81	0.01524	5.81378e-5	0.0	Linear
nLw_488	0.0	2.54	0.01016	3.87585e-5	0.0	Linear
nLw_490	0.0	2.54	0.01016	3.87585e-5	0.0	Linear
nLw_510	0.0	2.54	0.01016	3.87585e-5	0.0	Linear
nLw_520	0.0	5.08	0.02032	7.75170e-5	0.0	Linear
nLw_531	0.0	1.27	0.00508	1.93793e-5	0.0	Linear
nLw_550	0.0	1.27	0.00508	1.93793e-5	0.0	Linear
nLw_551	0.0	1.27	0.00508	1.93793e-5	0.0	Linear
nLw_555	0.0	1.27	0.00508	1.93793e-5	0.0	Linear
nLw_565	0.0	5.08	0.02032	7.75170e-5	0.0	Linear
nLw_667	0.0	1.016	0.004064	1.55034e-5	0.0	Linear
nLw_670	0.0	1.016	0.004064	1.55034e-5	0.0	Linear
chlor_a	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_oc2	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_oc3	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_oc4	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_ndpi	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_clark	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_carder	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
chlor_gsm01	0.01	64.5654	0.015240	5.81378e-5	-2.0	Log
K_490	0.01	6.223	0.011176	4.26344e-5	-2.0	Log
sst	-2.0	45.0	0.188	7.17185e-4	-2.0	Linear
sst4	-2.0	45.0	0.188	7.17185e-4	-2.0	Linear
par	0.0	76.2	0.3048	1.16275e-3	0.0	Linear
calcite	5.01187e-5	0.0559757	0.012192	4.65102e-5	-4.3	Log
calcite_2b	5.01187e-5	0.0559757	0.012192	4.65102e-5	-4.3	Log
calcite_3b	5.01187e-5	0.0559757	0.012192	4.65102e-5	-4.3	Log
flh	0.001	0.107647	0.0081280	3.10068e-5	-3.0	Log
ndvi	-0.35	0.92	0.00508	1.93793e-5	-0.35	Linear
evi	-0.35	0.92	0.00508	1.93793e-5	-0.35	Linear
eps_78	0.85	1.231	0.001524	5.81378e-5	0.85	Linear
angstrom_510	-0.1	1.4748	0.0062992	2.40303e-5	-0.1	Linear
angstrom_520	-0.1	1.4748	0.0062992	2.40303e-5	-0.1	Linear
angstrom_531	-0.1	1.4748	0.0062992	2.40303e-5	-0.1	Linear
tau_670	0.0	0.508	0.002032	7.75170e-5	0.0	Linear
tau_865	0.0	0.508	0.002032	7.75170e-5	0.0	Linear
tau_869	0.0	0.508	0.002032	7.75170e-5	0.0	Linear
taua_865	0.0	0.508	0.002032	7.75170e-5	0.0	Linear
taua_869	0.0	0.508	0.002032	7.75170e-5	0.0	Linear

Interactive Mode:

Main SMI Widget:

The main SMI widget can be accessed under then main SeaDAS Process pull down menu or from the seadas command line by typing "smigen".

Input File Selection Section:

Level-3 binned file	The input Level-3 binned file.  It can be either a space-binned or time-binned file. This entry can be typed in manually or interactively selected with the Select button.
Select	To interactively select an input file using the File Selection Widget. The file selected will be displayed in the Level-3 binned file input field.
Help	Display this HTML help file in local Netscape or Mosaic HTML viewer.
Quit	Quit the smigen GUI.

Current Working Product Entry Section: In this section, SMI output products are defined. The user can change all the output parameters such as product, latnorth, latsouth, lonwest, loneast, projection, resolution, measure, scaling and output filename until a desired output product is defined. Once an output product is defined, pressing the Add to Process List button adds the current product to the list for processing. As many output products can be added to the process list as desired. In addition, once an item has been added to the process list, it can be edited further by selecting the item with the left mouse button, modifying the information and then pressing the Update Process List button.

Products	The current working geo-physical parameter. When a product button is selected, the defaults for Measure and Scaling for that product are automatically loaded.  A default output file name is also automatically generated. (See Command Mode for a list of the scaling defaults.)
Latnorth	Northernmost latitude used for output.  (Default=90.0)
Latsouth	Southernmost latitude used for output.  (Default=-90.0)
Lonwest	Westernmost longitude used for output.  (Default=-180.0)
Loneast	Easternmost longitude used for output.  (Default=180.0)
Projection	Output projection type.  SIN or RECT  (Default=RECT).
Resolution	Output resolution.  SMI, SMI4, LAND, 36km, 9km, 4km, 2km, or 1km.   (Default=9km)
Precision	Output datatype.  BYTE (8-bit int), INT16 (16-bit int).  (Default=BYTE)
Measure	The statistical measure desired for the geo-physical parameter selected.  Note that measures pixels and scenes will produce exactly the same output across all geo-physical parameters for a given input file.  The following variables are stored for every bin in the L3-binned input file and are used in calculating the measures: s = sums of all values input to the bin ssq = sums of the squares of all input values to the bin wt = weight assigned to that bin ns = number of scenes input to that bin Mean s/wt Variance tmp_var = (ssq/wt)-(mean**2) var = (tmp_var * wt**2) / ((wt**2)-ns) Standard Deviation sqrt(var) Pixels Number of Level-2 input values that went into creating the Level-3 bin selected for each grid point Scenes Number of Level-2 input files that went into creating the Level-3 bin selected for each grid point
Scaling	The inputs to use for scaling the geo-physical product.  Modifying any of the scaling parameters will cause the others to automatically recalculate. ***NOTE: You must hit the enter key after entering these values!***  (See Command Mode for a list of the scaling defaults).
File Out	The name of the SMI HDF output file. (One output file per geo-physical product).
ASCII Palette File	The name of an alternate color palette to use instead of the default color table. (A blank denotes using the SMI default color palette).
Add To Process List	Add the current working product entry to the processing list.
Update Process List	Update the highlighted item in the processing list with the current information in the working product entry.

Products Selected For SMI Processing Section:

Products Selected List	Selecting an item in the processing list, will cause all the fields to be loaded back into the working product entry.
Delete Entry	Delete the highlighted item in the processing list.
Clear All	Delete all items from the processing list.

Job Submission Section:

Submit	Submit all items in the processing list for SMI processing in the background. Output messages will be printed to the specified Log File. If the log file entry is left blank, messages will print to the screen.
Run	Process all items listed in the processing list in the foreground. All output messages will be printed to the terminal screen. This option will tie up your terminal and may take several minutes depending on the number of bins in the input file.  It is not advisable to use this option.
Log File	The name of the logfile for smigen job submission. If blank, any log information will be printed to the screen.

Curator: OceanColor Webmaster Authorized by: gene carl feldman

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