ocmw.core.geometry module

Basic geometry tools used in the OCMW processes.

pol2cart	Coordinate conversion: Polar to Cartesian
cart2pol	Coordinate conversion: Cartesian to Polar
pol2cmplx	Coordinate conversion: Polar to Complex
cmplx2pol	Coordinate conversion: Complex to Polar
cart2cmplx	Coordinate conversion: Cartesian to Complex
cmplx2cart	Coordinate conversion: Complex to Cartesian
rotateVectorField	Rotate a set of vector field data about the z axis of the coordinate system.
unitVect	Get unit vector components parallel to the line join p1 and p1
circSign2D	Calculate the direction of circulation around a pair of edge vectors in the x-y plane.
spatialCoverage	Base class for setting spatial coverage of data in lat/lon ranges.

Basic geometry tools used in the OCMW processes.

class ocmw.core.geometry.spatialCoverage(lat_min, lat_max, lon_min, lon_max)

Bases: object

Base class for setting spatial coverage of data in lat/lon ranges.

ocmw.core.geometry.pol2cart(r, theta)

Coordinate conversion: Polar to Cartesian

Parameters:

• r (numpy.array, float) – radial distance

• theta (numpy.array, float) – angle in degrees

Returns:

• x (numpy.array, float) – cartesian x coordinate

• y (numpy.array, float) – cartesian y coordinate

ocmw.core.geometry.cart2pol(x, y)

Coordinate conversion: Cartesian to Polar

Parameters:

• x (numpy.array, float) – cartesian x coordindate

• y (numpy.array, float) – cartesian y coordinate

Returns:

• r (numpy.array, float) – polar cordinate radial distance

• theta (numpy.array, float) – polar cordinate angle (in degrees)

ocmw.core.geometry.pol2cmplx(radii, angles, angularUnits=0)

Coordinate conversion: Polar to Complex

Parameters:

• radii (numpy.array, float) – polar coordinate radial distances

• angles (numpy.array, float) – polar cordinate angles

• anglularUnits (int) – angular units flag (0 = degress [default], 1 = radians)

Returns:

cmplx (numpy.array, complex) – complex numbers (x + jy)

ocmw.core.geometry.cmplx2pol(x, angularUnits=0)

Coordinate conversion: Complex to Polar

Parameters:

• x (numpy.array, complex) – complex numbers (x + jy)

• anglularUnits (int) – angular units flag (0 = degress [default], 1 = radians)

Returns:

• radii (numpy.array, float) – polar coordinate radial values

• angles (numpy.array, float) – polar coordinate angle values

ocmw.core.geometry.cart2cmplx(x, y)

Coordinate conversion: Cartesian to Complex

Parameters:

• x (numpy.array, float) – cartesian x-coordinate

• y (numpy.array, float) – cartesian y coordinate

Returns:

cmplx (numpy.array, complex) – complex numbers (x + jy)

ocmw.core.geometry.cmplx2cart(c)

Coordinate conversion: Complex to Cartesian

Parameters:

c (numpy.array, complex) – complex numbers (x + jy)

Returns:

• x (numpy.array, float) – cartesian x coordinate

• y (numpy.array, float) – cartesian y cordinate

ocmw.core.geometry.rotateVectorField(U, V, W, Theta)

Rotate a set of vector field data about the z axis of the coordinate system.

Parameters:

• U (numpy.array, float) – array of vector field values along the x axis.

• V (numpy.array, float) – array of vector field values along the y axis.

• W (numpy.array, float) – array of vector field values along the z axis.

• Theta (float) – rotation angle in degrees (including sign for rotation direction).

Returns:

• Ur (numpy.array, float) – array of vector field values along the x axis in rotated coordinates.

• Vr (numpy.array, float) – array of vector field values along the y axis in rotated coordinates.

• Wr (numpy.array, float) – array of vector field values along the z axis in rotated coordinates.

ocmw.core.geometry.unitVect(p1, p2)

Get unit vector components parallel to the line join p1 and p1

Parameters:

• p1 (numpy.array,float) – vector containing cartesian coordinates of point p1.

• p2 (numpy.array,float) – vector containing cartesian coordinates of point p1.

Returns:

uVec (numpy.array, float) – vector containing cartesian coordinates of unit vector along (p1,p1).

ocmw.core.geometry.circSign2D(v1, v2)

Calculate the direction of circulation around a pair of edge vectors in the x-y plane.

Parameters:

• v1 (numpy.array,float) – components of edge vector v1 in cartesian coordinates.

• v2 (numpy.array,float) – components of edge vector v2 in cartesian coordinates.

Returns:

csgn (float) – sign of circulation direction (i.e. +/- 1).