Beispiel #1
0
def test_autocorrelate():
    """Test that auto-correlation works the same as convolution with the mirror image of itself.

    (See the Signal processing Section of http://en.wikipedia.org/wiki/Autocorrelation)
    """
    import time
    t1 = time.time()
    # Use a function that is NOT two-fold rotationally symmetric, e.g. two different flux Gaussians
    myGauss1 = galsim.SBGaussian(sigma=3., flux=4)
    myGauss1.applyShift(-0.2, -0.4)
    myGauss2 = (galsim.SBGaussian(sigma=6., flux=1.3))
    myGauss2.applyShift(0.3, 0.3)
    mySBP1 = galsim.SBAdd([myGauss1, myGauss2])
    mySBP2 = galsim.SBAdd([myGauss1, myGauss2])
    # Here we rotate by 180 degrees to create mirror image
    mySBP2.applyRotation(180. * galsim.degrees)
    myConv = galsim.SBConvolve([mySBP1, mySBP2])
    myImg1 = galsim.ImageF(80, 80, scale=0.7)
    myConv.draw(myImg1.view())
    myAutoCorr = galsim.SBAutoCorrelate(mySBP1)
    myImg2 = galsim.ImageF(80, 80, scale=0.7)
    myAutoCorr.draw(myImg2.view())
    printval(myImg1, myImg2)
    np.testing.assert_array_almost_equal(
        myImg1.array,
        myImg2.array,
        4,
        err_msg=
        "Asymmetric sum of Gaussians convolved with mirror of self disagrees with "
        + "SBAutoCorrelate result")

    # Repeat with the GSObject version of this:
    obj1 = galsim.Gaussian(sigma=3., flux=4)
    obj1.applyShift(-0.2, -0.4)
    obj2 = galsim.Gaussian(sigma=6., flux=1.3)
    obj2.applyShift(0.3, 0.3)
    add1 = galsim.Add(obj1, obj2)
    add2 = (galsim.Add(obj1, obj2)).createRotated(180. * galsim.degrees)
    conv = galsim.Convolve([add1, add2])
    conv.draw(myImg1)
    corr = galsim.AutoCorrelate(add1)
    corr.draw(myImg2)
    printval(myImg1, myImg2)
    np.testing.assert_array_almost_equal(
        myImg1.array,
        myImg2.array,
        4,
        err_msg=
        "Asymmetric sum of Gaussians convolved with mirror of self disagrees with "
        + "AutoCorrelate result")

    # Test photon shooting.
    do_shoot(corr, myImg2, "AutoCorrelate")

    t2 = time.time()
    print 'time for %s = %.2f' % (funcname(), t2 - t1)
Beispiel #2
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def test_smallshear():
    """Test the application of a small shear to a Gaussian SBProfile against a known result.
    """
    import time
    t1 = time.time()
    e1 = 0.02
    e2 = 0.02
    myShear = galsim.Shear(e1=e1, e2=e2)
    # test the SBProfile version using applyShear
    savedImg = galsim.fits.read(os.path.join(imgdir, "gauss_smallshear.fits"))
    myImg = galsim.ImageF(savedImg.bounds, scale=0.2)
    mySBP = galsim.SBGaussian(flux=1, sigma=1)
    mySBP.applyShear(myShear._shear)
    mySBP.draw(myImg.view())
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
            myImg.array, savedImg.array, 5,
            err_msg="Small-shear Gaussian profile disagrees with expected result")

    # Repeat with the GSObject version of this:
    gauss = galsim.Gaussian(flux=1, sigma=1)
    gauss.applyShear(myShear)
    gauss.draw(myImg,dx=0.2, normalization="surface brightness", use_true_center=False)
    np.testing.assert_array_almost_equal(
            myImg.array, savedImg.array, 5,
            err_msg="Using GSObject applyShear disagrees with expected result")
    gauss = galsim.Gaussian(flux=1, sigma=1)
    gauss2 = gauss.createSheared(myShear)
    gauss2.draw(myImg,dx=0.2, normalization="surface brightness", use_true_center=False)
    np.testing.assert_array_almost_equal(
            myImg.array, savedImg.array, 5,
            err_msg="Using GSObject createSheared disagrees with expected result")
 
    # Check with default_params
    gauss = galsim.Gaussian(flux=1, sigma=1, gsparams=default_params)
    gauss.applyShear(myShear)
    gauss.draw(myImg,dx=0.2, normalization="surface brightness", use_true_center=False)
    np.testing.assert_array_almost_equal(
            myImg.array, savedImg.array, 5,
            err_msg="Using GSObject applyShear with default_params disagrees with expected result")
    gauss = galsim.Gaussian(flux=1, sigma=1, gsparams=galsim.GSParams())
    gauss.applyShear(myShear)
    gauss.draw(myImg,dx=0.2, normalization="surface brightness", use_true_center=False)
    np.testing.assert_array_almost_equal(
            myImg.array, savedImg.array, 5,
            err_msg="Using GSObject applyShear with GSParams() disagrees with expected result")
 
    # Test photon shooting.
    do_shoot(gauss,myImg,"sheared Gaussian")

    # Test kvalues
    do_kvalue(gauss,"sheared Gaussian")

    t2 = time.time()
    print 'time for %s = %.2f'%(funcname(),t2-t1)
Beispiel #3
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def test_add():
    """Test the addition of two rescaled Gaussian profiles against a known double Gaussian result.
    """
    import time
    t1 = time.time()
    mySBP = galsim.SBGaussian(flux=0.75, sigma=1)
    mySBP2 = galsim.SBGaussian(flux=0.25, sigma=3)
    myAdd = galsim.SBAdd([mySBP, mySBP2])
    savedImg = galsim.fits.read(os.path.join(imgdir, "double_gaussian.fits"))
    myImg = galsim.ImageF(savedImg.bounds, scale=0.2)
    myAdd.draw(myImg.view())
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Addition of two rescaled Gaussian profiles disagrees with expected result"
    )

    # Repeat with the GSObject version of this:
    gauss1 = galsim.Gaussian(flux=0.75, sigma=1)
    gauss2 = galsim.Gaussian(flux=0.25, sigma=3)
    sum = galsim.Add(gauss1, gauss2)
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Add(gauss1,gauss2) disagrees with expected result")

    # Check with default_params
    sum = galsim.Add(gauss1, gauss2, gsparams=default_params)
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Add(gauss1,gauss2) with default_params disagrees with "
        "expected result")
    sum = galsim.Add(gauss1, gauss2, gsparams=galsim.GSParams())
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Add(gauss1,gauss2) with GSParams() disagrees with "
        "expected result")

    # Other ways to do the sum:
    sum = gauss1 + gauss2
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg="Using GSObject gauss1 + gauss2 disagrees with expected result"
    )
    sum = gauss1.copy()
    sum += gauss2
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject sum = gauss1; sum += gauss2 disagrees with expected result"
    )
    sum = galsim.Add([gauss1, gauss2])
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Add([gauss1,gauss2]) disagrees with expected result")
    gauss1 = galsim.Gaussian(flux=1, sigma=1)
    gauss2 = galsim.Gaussian(flux=1, sigma=3)
    sum = 0.75 * gauss1 + 0.25 * gauss2
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject 0.75 * gauss1 + 0.25 * gauss2 disagrees with expected result"
    )
    sum = 0.75 * gauss1
    sum += 0.25 * gauss2
    sum.draw(myImg,
             dx=0.2,
             normalization="surface brightness",
             use_true_center=False)
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject sum += 0.25 * gauss2 disagrees with expected result")

    # Test photon shooting.
    do_shoot(sum, myImg, "sum of 2 Gaussians")

    # Test kvalues
    do_kvalue(sum, "sum of 2 Gaussians")

    t2 = time.time()
    print 'time for %s = %.2f' % (funcname(), t2 - t1)
Beispiel #4
0
def test_realspace_shearconvolve():
    """Test the real-space convolution of a sheared Gaussian and a Box SBProfile against a 
       known result.
    """
    import time
    t1 = time.time()
    psf = galsim.SBGaussian(flux=1, sigma=1)
    e1 = 0.04
    e2 = 0.0
    myShear = galsim.Shear(e1=e1, e2=e2)
    psf.applyShear(myShear._shear)
    pix = galsim.SBBox(xw=0.2, yw=0.2, flux=1.)
    conv = galsim.SBConvolve([psf, pix], real_space=True)
    saved_img = galsim.fits.read(
        os.path.join(imgdir, "gauss_smallshear_convolve_box.fits"))
    img = galsim.ImageF(saved_img.bounds, scale=0.2)
    conv.draw(img.view())
    printval(img, saved_img)
    np.testing.assert_array_almost_equal(
        img.array,
        saved_img.array,
        5,
        err_msg=
        "Sheared Gaussian convolved with Box SBProfile disagrees with expected result"
    )

    # Repeat with the GSObject version of this:
    psf = galsim.Gaussian(flux=1, sigma=1)
    psf.applyShear(e1=e1, e2=e2)
    pixel = galsim.Pixel(xw=0.2, yw=0.2, flux=1.)
    conv = galsim.Convolve([psf, pixel], real_space=True)
    conv.draw(img,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        img.array,
        saved_img.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) disagrees with expected result")

    # Check with default_params
    conv = galsim.Convolve([psf, pixel],
                           real_space=True,
                           gsparams=default_params)
    conv.draw(img,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        img.array,
        saved_img.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) with default_params disagrees with "
        "expected result")
    conv = galsim.Convolve([psf, pixel],
                           real_space=True,
                           gsparams=galsim.GSParams())
    conv.draw(img,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        img.array,
        saved_img.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) with GSParams() disagrees with "
        "expected result")

    # Other ways to do the convolution:
    conv = galsim.Convolve(psf, pixel, real_space=True)
    conv.draw(img,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        img.array,
        saved_img.array,
        5,
        err_msg=
        "Using GSObject Convolve(psf,pixel) disagrees with expected result")

    # The real-space convolution algorithm is not (trivially) independent of the order of
    # the two things being convolved.  So check the opposite order.
    conv = galsim.Convolve([pixel, psf], real_space=True)
    conv.draw(img,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        img.array,
        saved_img.array,
        5,
        err_msg=
        "Using GSObject Convolve([pixel,psf]) disagrees with expected result")

    t2 = time.time()
    print 'time for %s = %.2f' % (funcname(), t2 - t1)
Beispiel #5
0
def test_shearconvolve():
    """Test the convolution of a sheared Gaussian and a Box SBProfile against a known result.
    """
    import time
    t1 = time.time()
    e1 = 0.04
    e2 = 0.0
    myShear = galsim.Shear(e1=e1, e2=e2)
    # test at SBProfile level using applyShear
    mySBP = galsim.SBGaussian(flux=1, sigma=1)
    mySBP.applyShear(myShear._shear)
    mySBP2 = galsim.SBBox(xw=0.2, yw=0.2, flux=1.)
    myConv = galsim.SBConvolve([mySBP, mySBP2])
    savedImg = galsim.fits.read(
        os.path.join(imgdir, "gauss_smallshear_convolve_box.fits"))
    myImg = galsim.ImageF(savedImg.bounds, scale=0.2)
    myConv.draw(myImg.view())
    printval(myImg, savedImg)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Sheared Gaussian convolved with Box SBProfile disagrees with expected result"
    )

    # Repeat with the GSObject version of this:
    psf = galsim.Gaussian(flux=1, sigma=1)
    psf2 = psf.createSheared(e1=e1, e2=e2)
    psf.applyShear(e1=e1, e2=e2)
    pixel = galsim.Pixel(xw=0.2, yw=0.2, flux=1.)
    conv = galsim.Convolve([psf, pixel])
    conv.draw(myImg,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) disagrees with expected result")
    conv2 = galsim.Convolve([psf2, pixel])
    conv2.draw(myImg,
               dx=0.2,
               normalization="surface brightness",
               use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) disagrees with expected result")

    # Check with default_params
    conv = galsim.Convolve([psf, pixel], gsparams=default_params)
    conv.draw(myImg,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) with default_params disagrees with "
        "expected result")
    conv = galsim.Convolve([psf, pixel], gsparams=galsim.GSParams())
    conv.draw(myImg,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Convolve([psf,pixel]) with GSParams() disagrees with "
        "expected result")

    # Other ways to do the convolution:
    conv = galsim.Convolve(psf, pixel)
    conv.draw(myImg,
              dx=0.2,
              normalization="surface brightness",
              use_true_center=False)
    np.testing.assert_array_almost_equal(
        myImg.array,
        savedImg.array,
        5,
        err_msg=
        "Using GSObject Convolve(psf,pixel) disagrees with expected result")

    # Test photon shooting.
    do_shoot(conv, myImg, "sheared Gaussian * Pixel")

    t2 = time.time()
    print 'time for %s = %.2f' % (funcname(), t2 - t1)