ncgrid

Interpolate dated polygon map series to a 3-d (x,y,t) lattice (netcdf file)

Usage

ncgrid.py {Create,Sample,Raster} [command options]

Command	Description
create	Create x,y,t netcdf file from an input raster and date series
sample	Sample dated polygon map series at x,y,t grid coordinates.
raster	Sample x,y raster at netcdf x,y grid coordinates

Create

Create x,y,t lattice netcdf file.

Parameter	Description
ncfile	Created netcdf file path
raster	Input raster file. Defines xy lattice
start	Start date YYYY-MM-DD
end	End date YYYY-MM-DD
freq	Time dimension frequency [DAILY,WEEKLY,MONTHLY,YEARLY]
tunit	time units (default = "days since 1900-01-01 00:00:00")
ttype	time data type (default = "i4")

sample

sample dated polygon map series to netcdf grid using a query.

Parameter	Description
ncfile	Netcdf file path
varname	Created variable name
infeatures	Input polygon shapefile path
target	Extracted variable field name
ineq	Inequality used in query [<,<=,>=,>]
priority	Priority field if multiple polygons match query
datefield	Input date field name
dateformat	Input date format string (%Y-%m-%d)
dtype	Created variable data type
--revpri	Reverse priority (-1 * priority)

Query

For each date in the time dimension
select polygons where *polyDate* is *ineq* *gridDate*
extract *targetfield* (choosing max *priorityfield* if n>1')

option --revpri should be used in queries of the 'next' feature of interest (earliest feature that is greater than current date).

raster

Add a single raster variable to existing netcdf file

Parameter	Description
ncfile	Netcdf file path
varname	Created variable name
raster	Input raster
dtype	Data type