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The software package is currently being dramatically improved and updated.
This is a (very) old version, potentially with bugs.

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Source code for simage_make_shapelet_object.pro:

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function simage_make_shapelet_object,decomp,$ gamma_input=gamma_input,psf=psf,inst_shear=inst_shear,$ rpos=rpos,seed=seed,shapeinfo=shapeinfo ;$Id: simage_make_shapelet_object.pro, v1.0$ ; ; Copyright 2004 Richard Massey and Alexandre Refregier. ; ; This file is a part of the Shapelets analysis code. ; www.ast.cam.ac.uk/~rjm/shapelets/ ; ; The Shapelets code is free software; you can redistribute it and/or ; modify it under the terms of the GNU General Public License as published ; by the Free Software Foundation; either version 2 of the License, or ; (at your option) any later version. ; ; The Shapelets code 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 General Public License for more details. ; ; You should have received a copy of the GNU General Public License ; along with the Shapelets code; if not, write to the Free Software ; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA ; ;+ ; NAME: ; SIMAGE_MAKE_SHAPELET_OBJECT ; ; CATEGORY: ; Shapelet simulated images. ; ; PURPOSE: ; This module makes one object for the shapelet-based image simulations, using ; a full shapelet model of its morphology. It is pixellated using various ; input parameters. ; ; INPUTS: ; decomp - Cartesian shapelet decomp structure of the resampled galaxy. ; ; OPTIONAL INPUTS: ; gamma - Weak lensing shear on all galaxies [gamma1,gamma2]. ; psf - Cartesian decomp structure representing PSF. Will then do ; convolvution automatically. Stars are just this PSF. ; instrum - Post-smear shear due to geometric distortions in telescope. ; seed - Seed for random number generator. ; ; KEYWORD PARAMETERS: ; RPOS - Randomise positions and PAs of galaxies? ; ; OUTPUTS: ; recomp - One (shapelet) simulated object in a postage stamp image. ; shapeinfo - A structure containing object properties for inclusion in the ; pre-noise catalogue. ; ; MODIFICATION HISTORY: ; Jun 03 - Written by Richard Massey ;- COMPILE_OPT idl2 ; Rotate object randomly if the positions are also random. if keyword_set(rpos) then shapelets_rotate,decomp,(randomu(seed)*360.) ; Shear object (weak lensing). if keyword_set(gamma_input) then begin shapelets_extend_nmax,decomp,2 shapelets_shear,decomp,gamma_input n_max_g=decomp.n_max endif else n_max_g=decomp.n_max+2 ; Smear object (atmospheric + telescope PSF). if keyword_set(psf) then decomp=convolution(decomp,psf,n_max_g=n_max_g) ; Shear object (instrumental distortions). if keyword_set(inst_shear) then sshear,decomp,inst_shear ; Re-compose the object into pixels. shapelets_recomp, decomp, recomp ; Make sure we do not truncate the edges of the object as would bias shape measurement. while total(abs(recomp[*,0]))+$ total(abs(recomp[0,*]))+$ total(abs(recomp[decomp.n_pixels[0]-1,*]))+$ total(abs(recomp[*,decomp.n_pixels[1]-1])) $ gt (1e-10>abs(max(recomp)/1e7)) do begin decomp.n_pixels=decomp.n_pixels+[10,10] decomp.x=decomp.x+[5.,5.] shapelets_recomp, decomp, recomp endwhile ; Calculate (pre-noise) shape properties for posterity q=shapelets_quadrupole(decomp,flux=flux) rsq=(Q[0,0]+Q[1,1])/flux ell=complex(Q[0,0]-Q[1,1],2*Q[0,1])/(Q[0,0]+Q[1,1]) PA=atan(imaginary(ell),float(ell))/2.+!pi/2 A=sqrt(rsq*(1+abs(ell))/2.) B=sqrt(abs(rsq*(1-abs(ell))/2.)) shapeinfo={A:A,B:B,theta:(PA*180/!pi) mod 360-90,rsq:rsq,flux:flux,mag:-2.5*alog10(flux)+22.08} ; That`s all folks! return, recomp end

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Last modified on 02nd May 2008 by Richard Massey.

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