Modland.jl

MODIS/VIIRS Sinusoidal Land Tile Utilities for Julia

Gregory H. Halverson (they/them)
gregory.h.halverson@jpl.nasa.gov
Lead developer and designer
NASA Jet Propulsion Laboratory

Overview

This Julia module provides functions for converting geographic latitude and longitude coordinates to sinusoidal projection coordinates and mapping those to MODIS land tile indices.

Installation

Ensure that you have the required dependencies installed before using this module. You may need to install libraries such as ArchGDAL.jl for coordinate transformations.

Usage

latlon_to_sinusoidal

Converts latitude and longitude coordinates to sinusoidal projection coordinates.

latlon_to_sinusoidal(lat::Float64, lon::Float64)::Tuple{Float64, Float64}

Arguments

• lat::Float64: Latitude in degrees (-90 to 90).
• lon::Float64: Longitude in degrees (-180 to 180).

Returns

• Tuple{Float64, Float64}: Sinusoidal projection coordinates (x, y).

Example

x, y = latlon_to_sinusoidal(34.0, -118.0)
println("Sinusoidal Coordinates: ($x, $y)")

Error Handling

• Raises an error if latitude is out of range (-90 to 90).
• Raises an error if longitude is out of range (-180 to 180).

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sinusoidal_to_modland

Converts sinusoidal projection coordinates to MODIS land tile indices.

sinusoidal_to_modland(x::Float64, y::Float64)::String

Arguments

• x::Float64: Sinusoidal x coordinate.
• y::Float64: Sinusoidal y coordinate.

Returns

• String: MODIS land tile index formatted as hXXvYY.

Example

tile_index = sinusoidal_to_modland(x, y)
println("MODIS Tile Index: $tile_index")

Error Handling

• Raises an error if x is outside the valid bounds.
• Raises an error if y is outside the valid bounds.