sphunif (version 1.4.3)

venus: Venus craters

Description

Craters on Venus from the USGS Astrogeology Science Center.

Usage

venus

Format

A data frame with 967 rows and 4 variables:

name

name of the crater (if named).

diameter

diameter of the crater (in km).

theta

longitude angle \(\theta \in [0, 2\pi)\) of the crater center.

phi

latitude angle \(\phi \in [-\pi/2, \pi/2]\) of the crater center.

Details

The \((\theta, \phi)\) angles are such their associated planetocentric coordinates are: $$(\cos(\phi) \cos(\theta), \cos(\phi) \sin(\theta), \sin(\phi))',$$ with \((0, 0, 1)'\) denoting the north pole.

The script performing the data preprocessing is available at venus.R.

Examples

# Load data
data("venus")

# Add Cartesian coordinates
venus$X <- cbind(cos(venus$theta) * cos(venus$phi),
                 sin(venus$theta) * cos(venus$phi),
                 sin(venus$phi))

# Tests
unif_test(data = venus$X, type = c("PCvM", "PAD", "PRt"), p_value = "asymp")