astropy适合多个标题

Question

我试图用Python创建一个FITS文件，但是在将头文件和PrimaryHDU一起编译时似乎遇到了问题。在

我做了一个简单的例子，给出了我得到的错误：

import numpy as np
from astropy.io import fits

a = np.ones([5,5])
hdu = fits.PrimaryHDU(a)
hdr = fits.Header()
hdr['NPIX1'] = 60
hdr['NPIX2'] = 60
hdr['CRPIX1'] = 0
hdr['CRPIX2'] = 0
primary_hdu = fits.PrimaryHDU(header=hdr)
hdul = fits.HDUList([primary_hdu, hdu])
hdul.writeto('table4.fits')

运行此代码时，出现以下错误：

VerifyError: Verification reported errors: HDUList's element 1 is not an extension HDU. Note: astropy.io.fits uses zero-based indexing.

我看到一些帖子声称这可能是因为PrimaryHDU需要在HDUList中第一个导出，但是看看我的代码，我相信我已经做到了。在

如有任何帮助，我们将不胜感激，谢谢。在

Answer 1

请注意错误消息：

VerifyError: Verification reported errors: HDUList's element 1 is not an extension HDU. Note: astropy.io.fits uses zero-based indexing.

HDUList中的第二项是也是aPrimaryHDU，这不是一个有效的扩展HDU（Primary在这里基本上意味着第一个和唯一的）。在

使HDU成为ImageHDU，事情就会起作用：

import numpy as np
from astropy.io import fits

a = np.ones([5,5])
hdu = fits.ImageHDU(a)     # Don't use a `PrimaryHDU` here
hdr = fits.Header()
hdr['NPIX1'] = 60
hdr['NPIX2'] = 60
hdr['CRPIX1'] = 0
hdr['CRPIX2'] = 0
primary_hdu = fits.PrimaryHDU(header=hdr)
hdul = fits.HDUList([primary_hdu, hdu])
hdul.writeto('table4.fits')