shesha.init.atmos_init Namespace Reference

Initialization of a Atmos object. More...

Functions
def	atmos_init (carmaWrap_context context, conf.Param_atmos p_atmos, conf.Param_tel p_tel, conf.Param_geom p_geom, ittime=None, p_wfss=None, p_targets=None, dataBase={}, use_DB=False)
	Initializes an Atmos object. More...

Detailed Description

Initialization of a Atmos object.

Author

COMPASS Team https://github.com/ANR-COMPASS

Version

5.0.0

Date

2020/05/18

Copyright

GNU Lesser General Public License

This file is part of COMPASS https://anr-compass.github.io/compass/

Copyright (C) 2011-2019 COMPASS Team https://github.com/ANR-COMPASS All rights reserved. Distributed under GNU - LGPL

COMPASS is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version.

COMPASS: End-to-end AO simulation tool using GPU acceleration The COMPASS platform was designed to meet the need of high-performance for the simulation of AO systems.

The final product includes a software package for simulating all the critical subcomponents of AO, particularly in the context of the ELT and a real-time core based on several control approaches, with performances consistent with its integration into an instrument. Taking advantage of the specific hardware architecture of the GPU, the COMPASS tool allows to achieve adequate execution speeds to conduct large simulation campaigns called to the ELT.

The COMPASS platform can be used to carry a wide variety of simulations to both testspecific components of AO of the E-ELT (such as wavefront analysis device with a pyramid or elongated Laser star), and various systems configurations such as multi-conjugate AO.

COMPASS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with COMPASS. If not, see https://www.gnu.org/licenses/lgpl-3.0.txt.

Function Documentation

atmos_init()

def shesha.init.atmos_init.atmos_init	(	carmaWrap_context	context,
		conf.Param_atmos	p_atmos,
		conf.Param_tel	p_tel,
		conf.Param_geom	p_geom,
			ittime = None,
			p_wfss = None,
			p_targets = None,
			dataBase = {},
			use_DB = False
	)

Initializes an Atmos object.

:parameters: context (carmaWrap_context): GPU device context p_atmos (Param_atmos): Atmosphere parameters p_tel (Param_tel): Telescope parameters p_geom (Param_geom): Geometry parameters ittime (float): (optional) exposition time [s] p_wfss (list of Param_wfs): (optional) WFS parameters p_targets (list of Param_target): (optional) target parameters dataBase (dict): (optional) dictionary for data base use_DB (bool): (optional) flag for using the dataBase system :return: atm (Atmos): Atmos object

Definition at line 63 of file atmos_init.py.

    :return:
        atm : (Atmos): Atmos object
    """
    if not p_geom.is_init:
        raise RuntimeError("Cannot init atmosphere with uninitialized p_geom.")
 
    # Deleted carmaWrap_context : get the singleton
 
    if p_atmos.r0 is None:
        p_atmos.r0 = 0.
 
    if ittime is None:
        ittime = 1.
    # Adjust layers alt using zenith angle
    p_atmos.alt = p_atmos.alt / np.cos(p_geom.zenithangle * CONST.DEG2RAD)
    # Pixel size in meters
    p_atmos.pupixsize = p_tel.diam / p_geom.pupdiam
 
    # Off-axis wavefront sensors and targets
    # Note : p_wfss is a list of single-WFS configs
    #        but p_target groups several targets
    #        hence different xpos, ypos syntaxes
    norms = [0.]
    if p_wfss is not None:
        norms += [(w.xpos**2 + w.ypos**2)**0.5 for w in p_wfss]
    if p_targets is not None:
        norms += [(p_target.xpos**2 + p_target.ypos**2)**0.5 for p_target in p_targets]
 
    max_size = max(norms)
 
    # Meta-pupil diameter for all layers depending on altitude
    patch_diam = (p_geom._n + 2 * (max_size * CONST.ARCSEC2RAD * p_atmos.alt) /
                  p_atmos.pupixsize + 4).astype(np.int64)
    p_atmos.dim_screens = (patch_diam + patch_diam % 2)
 
    # Phase screen speeds
    lin_delta = p_geom.pupdiam / p_tel.diam * p_atmos.windspeed * \
        np.cos(CONST.DEG2RAD * p_geom.zenithangle) * ittime
    p_atmos._deltax = lin_delta * np.sin(CONST.DEG2RAD * p_atmos.winddir + np.pi)
    p_atmos._deltay = lin_delta * np.cos(CONST.DEG2RAD * p_atmos.winddir + np.pi)
 
    # Fraction normalization
    p_atmos.frac /= np.sum(p_atmos.frac)
 
    if p_atmos.L0 is None:
        # Set almost infinite L0
        p_atmos.L0 = np.ones(p_atmos.nscreens, dtype=np.float32) * 1e5
    L0_pix = p_atmos.L0 * p_geom.pupdiam / p_tel.diam
 
    if p_atmos.seeds is None:
        p_atmos.seeds = np.arange(p_atmos.nscreens, dtype=np.int64) + 1234
 
    r0_layers = p_atmos.r0 / (p_atmos.frac**(3. / 5.) * p_atmos.pupixsize)
    stencil_size = itK.stencil_size_array(p_atmos.dim_screens)
 
    atm = Atmos(context, p_atmos.nscreens, p_atmos.r0, r0_layers, p_atmos.dim_screens,
                stencil_size, p_atmos.alt, p_atmos.windspeed, p_atmos.winddir,
                p_atmos._deltax, p_atmos._deltay, context.active_device)
 
    print("Creating turbulent layers :")
    for i in tqdm(range(p_atmos.nscreens)):
        if "A" in dataBase:
            A, B, istx, isty = h5u.load_AB_from_dataBase(dataBase, i)
        else:
            A, B, istx, isty = itK.AB(p_atmos.dim_screens[i], L0_pix[i],
                                      p_atmos._deltax[i], p_atmos._deltay[i], 0)
            if use_DB:
                h5u.save_AB_in_database(i, A, B, istx, isty)
 
        atm.init_screen(i, A, B, istx, isty, p_atmos.seeds[i])
 
    return atm