# psychopy.tools.coordinatetools¶

Functions and classes related to coordinate system conversion

 cart2pol(x, y[, units]) Convert from cartesian to polar coordinates. cart2sph(z, y, x) Convert from cartesian coordinates (x,y,z) to spherical (elevation, azimuth, radius). pol2cart(theta, radius[, units]) Convert from polar to cartesian coordinates. sph2cart(*args) Convert from spherical coordinates (elevation, azimuth, radius) to cartesian (x,y,z).

## Function details¶

psychopy.tools.coordinatetools.cart2pol(x, y, units='deg')

Convert from cartesian to polar coordinates.

Usage: theta, radius = cart2pol(x, y, units=’deg’)

units refers to the units (rad or deg) for theta that should be returned

psychopy.tools.coordinatetools.cart2sph(z, y, x)

Convert from cartesian coordinates (x,y,z) to spherical (elevation, azimuth, radius). Output is in degrees.

usage:

array3xN[el,az,rad] = cart2sph(array3xN[x,y,z]) OR elevation, azimuth, radius = cart2sph(x,y,z)

If working in DKL space, z = Luminance, y = S and x = LM

Convert from polar to cartesian coordinates.

usage:

x,y = pol2cart(theta, radius, units='deg')
psychopy.tools.coordinatetools.sph2cart(*args)

Convert from spherical coordinates (elevation, azimuth, radius) to cartesian (x,y,z).

usage:
array3xN[x,y,z] = sph2cart(array3xN[el,az,rad]) OR x,y,z = sph2cart(elev, azim, radius)