python - 运行 Galsim 时的 FFT 运行时错误

Question

运行脚本保存动画时，我不断收到以下错误:

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.

所以我进入了/Galsim/include/galsim/GSparams.h

我更改了以下内容

从 maximum_fft_size(4096) 到 maximum_fft_size(16384)

或 2^12 中的 2^14。

我仍然得到和以前一样的错误。我应该重新启动我的机器还是什么？

Answer 1

这不是更改 maximum_fft_size 参数的地方。有关如何使用 GSParams 对象和更新参数的示例，请参见 demo7。 GSObject 的文档字符串中还有一个示例:

    >>> 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')