psfsim.wfi_coordinate_transformations

Utilities for WFI coordinate systems.

Functions

_from_angle_to_fpa(xan, yan[, wavelength])

Coarse transformation from field angle to FPA position.

from_angle_to_fpa(xan, yan[, wavelength, ray_trace, ...])

Full transformation from field angle to FPA position.

_from_fpa_to_angle(fpapos[, wavelength])

Coarse transformation from FPA position to field angle.

from_fpa_to_angle(fpapos[, wavelength, ray_trace, ...])

Full transformation from FPA position to field angle.

from_sca_to_fpa(scanum, scax, scay)

Coordinate transformation converting SCA to FPA coordinates.

from_sca_to_analysis(scanum, scax, scay)

Coordinate transformation converting SCA coordinates (in mm) to Analysis coordinates (in microns).

Module Contents

_from_angle_to_fpa(xan, yan, wavelength=0.48)[source]

Coarse transformation from field angle to FPA position.

Parameters:

  • xan (float) – Field positions in degrees.

  • yan (float) – Field positions in degrees.

  • wavelength (float, optional) – Vacuum wavelength in microns.

Returns:

Focal plane position in mm.

Return type:

(float, float)

from_angle_to_fpa(xan, yan, wavelength=0.48, ray_trace=True, use_filter='H', idealgeom=False)[source]

Full transformation from field angle to FPA position.

Parameters:

  • xan (float) – Field positions in degrees.

  • yan (float) – Field positions in degrees.

  • wavelength (float, optional) – Vacuum wavelength in microns.

  • ray_trace (bool, optional) – Whether to use ray tracing. (Default recommended for accuracy.)

  • use_filter (char, optional) – One-character code for which filter to use.

  • idealgeom (bool, optional) – Forces the design model rather than with the best-fit offsets.

Returns:

Focal plane position in mm.

Return type:

(float, float)

_from_fpa_to_angle(fpapos, wavelength=0.48)[source]

Coarse transformation from FPA position to field angle.

Parameters:

  • fpapos ((float, float)) – Focal plane position in mm.

  • wavelength (float, optional) – Vacuum wavelength in microns.

Returns:

Field positions in degrees.

Return type:

(float, float)

from_fpa_to_angle(fpapos, wavelength=0.48, ray_trace=True, use_filter='H', idealgeom=False)[source]

Full transformation from FPA position to field angle.

Parameters:

  • fpapos ((float, float)) – Focal plane position in mm.

  • wavelength (float, optional) – Vacuum wavelength in microns.

  • ray_trace (bool, optional) – Whether to use ray tracing. (Default recommended for accuracy.)

  • use_filter (char, optional) – One-character code for which filter to use.

  • idealgeom (bool, optional) – Forces the design model rather than with the best-fit offsets.

Returns:

Field positions in degrees.

Return type:

(float, float)

from_sca_to_fpa(scanum, scax, scay)[source]

Coordinate transformation converting SCA to FPA coordinates.

The “SCA” coordinates are aligned with the SOC “Science” frame (i.e., 180 degrees rotated relative to the FPA frame).

Parameters:

  • scanum (int) – The SCA number (1 through 18).

  • scax (float) – SCA coordinates in mm: (0, 0) is the center.

  • scay (float) – SCA coordinates in mm: (0, 0) is the center.

Returns:

The FPA coordinates in mm.

Return type:

(float, float)

from_sca_to_analysis(scanum, scax, scay)[source]

Coordinate transformation converting SCA coordinates (in mm) to Analysis coordinates (in microns).

The “SCA” coordinates are aligned with the SOC “Science” frame (i.e., 180 degrees rotated relative to the FPA frame).

The Analysis coordinates system is defined to be the FPA coordinate system with origin shifted to the center of the SCA.

Parameters:

  • scanum (int) – The SCA number (1 through 18).

  • scax (float) – SCA coordinates in mm: (0, 0) is the center.

  • scay (float) – SCA coordinates in mm: (0, 0) is the center.

Returns:

The analysis coordinates in microns.

Return type:

(float, float)