Question

我正在尝试解析以this逗号分隔的内容，其中列出了HiPS的一些调查。这是我的代码：

with open('surveys.txt') as data:
    text = data.read()
    surveys = OrderedDict()
    for survey in text.split('\n'):
        for line in survey.split('\n'):
            # Skip empty or comment lines
            if line == '' or line.startswith('#'):
                continue
            try:
                key, value = [_.strip() for _ in line.split('=')]
                surveys[key] = value
            except ValueError:
                continue

给我一个OrderedDict，其中包含上次调查的元素。这是因为在每次循环迭代后，surveys的内容被覆盖。

我尝试通过为每个新OrderedDict创建survey并使用以下代码将其附加到list来解决此问题：

with open('surveys.txt') as data:
    text = data.read()
    surveys = []
    for survey in text.split('\n'):
        survey_OD = OrderedDict()
        for line in survey.split('\n'):
            # Skip empty or comment lines
            if line == '' or line.startswith('#'):
                continue
            try:
                key, value = [_.strip() for _ in line.split('=')]
                survey_OD[key] = value
            except ValueError:
                continue
        surveys.append(survey_OD)

但是这会为每个逗号分隔值创建一个单独的OrderedDict，如下所示：

OrderedDict([('hips_order', '3')]) OrderedDict([('hips_frame', 'galactic')]) OrderedDict([('hips_tile_format', 'jpeg fits')])

什么时候，我期待这样的事情：

OrderedDict([('hips_order', '3'), ('hips_frame', 'galactic'), ('hips_tile_format', 'jpeg fits')])

Answer 1

让我们稍微改进你的第一种方法：

以双线换字符分开调查，
在列表中收集调查。

所以我们可以写

from collections import OrderedDict

with open('surveys.txt') as data:
    text = data.read()
surveys = list()
for raw_survey in text.split('\n\n'):
    survey = OrderedDict()
    # Skip empty lines
    for line in filter(None, raw_survey.split('\n')):
        # Skip comment lines
        if line.startswith('#'):
            continue
        try:
            key, value = [_.strip() for _ in line.split('=')]
            survey[key] = value
        except ValueError:
            continue
    surveys.append(survey)

会给我们

>>>surveys[0]
OrderedDict([('ID', 'CDS/C/MUSE-M42'), ('creator_did', 'ivo://CDS/C/MUSE-M42'),
             ('obs_collection', 'MUSE-M42'),
             ('obs_title', 'MUSE map of the central Orion Nebula (M 42)'), (
             'obs_description',
             'Integral-field spectroscopic dataset of the central part of the Orion Nebula (M 42), observed with the MUSE instrument at the ESO VLT (reduced the data with the public MUSE pipeline) representing a FITS cube with a spatial size of ~5.9\'x4.9\' (corresponding to ~0.76 pc x 0.63 pc) and a contiguous wavelength coverage of 4595...9366 Angstrom, spatially sampled at 0.2", with a sampling of 1.25 Angstrom in dispersion direction.'),
             ('obs_ack', 'Based on data obtained from the ESO/VLT'),
             ('prov_progenitor', 'MUSE Consortium'),
             ('bib_reference', '2015A&A...582A.114W'),
             ('obs_copyright', 'Copyright mention of the original data'),
             ('obs_copyright_url', 'http://muse-vlt.eu/science/m42/'),
             ('hips_release_date', '2015-07-07T00:29Z'),
             ('hips_builder', 'Aladin/HipsGen v9.505'), ('hips_order', '12'),
             ('hips_pixel_cut', '0 7760'), ('hips_tile_format', 'png fits'),
             ('hips_cube_depth', '3818'), ('hips_cube_firstframe', '1909'),
             ('hips_frame', 'equatorial'), ('dataproduct_type', 'image'),
             ('t_min', '56693'), ('t_max', '56704'), ('em_min', '4,595e-7'),
             ('em_max', '9,366e-7'), ('hips_version', '1.31'),
             ('hips_creation_date', '03/07/15 12:00:30'),
             ('hips_creator', 'CDS (P.Fernique)'), ('hips_tile_width', '512'),
             ('hips_status', 'public master clonableOnce'),
             ('hips_pixel_bitpix', '-32'), ('data_pixel_bitpix', '-32'),
             ('hips_hierarchy', 'mean'), ('hips_initial_ra', '83.82094'),
             ('hips_initial_dec', '-5.39542'), ('hips_initial_fov', '0.09811'),
             ('hips_pixel_scale', '2.795E-5'), ('s_pixel_scale', '5.555E-5'),
             ('moc_sky_fraction', '2.980E-7'), ('hips_estsize', '87653'),
             ('data_bunit', '10**(-20)*erg/s/cm**2/Angstrom'),
             ('data_cube_crpix3', '1'), ('data_cube_crval3', '4595'),
             ('data_cube_cdelt3', '1.25'), ('data_cube_bunit3', 'Angstrom'),
             ('client_application', 'AladinDesktop'),
             ('hips_copyright', 'CNRS/Unistra'), ('obs_regime', 'Optical'),
             ('hips_service_url', 'http://alasky.unistra.fr/MUSE/MUSE-M42'), (
             'hips_service_url_1',
             'http://alaskybis.unistra.fr/MUSE/MUSE-M42'),
             ('hips_status_1', 'public mirror clonable'), (
             'hips_service_url_2',
             'https://alaskybis.unistra.fr/MUSE/MUSE-M42'),
             ('hips_status_2', 'public mirror clonable'), ('moc_order', '12'),
             ('obs_initial_ra', '83.82094'), ('obs_initial_dec', '-5.39542'),
             ('obs_initial_fov', '0.014314526715905856'),
             ('TIMESTAMP', '1490387811000')])

创建OrderedDicts列表

1 个答案: