运行Galsim的FFT运行时误差

Question

在运行脚本以保存动画时，我一直收到以下错误：

RuntimeError: SB Error: fourierDraw() requires an FFT that is too large, 6144
If you can handle the large FFT, you may update gsparams.maximum_fft_size.

因此，我进入了/galsim/include/galsim/GSaffs.h

我修改了下面的内容

maximum_fft_size(16384)来自maximum_fft_size(4096)

或2^12中的2^14。

我仍然会遇到和以前一样的错误。我该重新启动我的机器吗？

Answer 1

这不是要更改maximum_fft_size参数的地方。有关如何使用demo7对象和更新参数的示例，请参阅GSParams。在GSObject的doc字符串中也有一个示例：

    >>> gal = galsim.Sersic(n=4, half_light_radius=4.3)
    >>> psf = galsim.Moffat(beta=3, fwhm=2.85)
    >>> conv = galsim.Convolve([gal,psf])
    >>> im = galsim.Image(1000,1000, scale=0.05)        # Note the very small pixel scale!
    >>> im = conv.drawImage(image=im)                   # This uses the default GSParams.
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File "galsim/base.py", line 1236, in drawImage
        image.added_flux = prof.SBProfile.draw(imview.image, gain, wmult)
    RuntimeError: SB Error: fourierDraw() requires an FFT that is too large, 6144
    If you can handle the large FFT, you may update gsparams.maximum_fft_size.
    >>> big_fft_params = galsim.GSParams(maximum_fft_size=10240)
    >>> conv = galsim.Convolve([gal,psf],gsparams=big_fft_params)
    >>> im = conv.drawImage(image=im)                   # Now it works (but is slow!)
    >>> im.write('high_res_sersic.fits')