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外部ライブラリを使用せずに、次のような arff ファイルを解析する必要があります。属性を数値に関連付ける方法がわかりません。各行の最初の数値が年齢で、2 番目の数値が性別であるとどのように言えますか? 同様のシナリオを解析するための python コードをいくつかリンクしてもらえますか?

@relation cleveland-14-heart-disease
@attribute 'age' real
@attribute 'sex' { female, male}
@attribute 'cp' { typ_angina, asympt, non_anginal, atyp_angina}
@attribute 'trestbps' real
@attribute 'chol' real
@attribute 'fbs' { t, f}
@attribute 'restecg' { left_vent_hyper, normal, st_t_wave_abnormality}
@attribute 'thalach' real
@attribute 'exang' { no, yes}
@attribute 'oldpeak' real
@attribute 'slope' { up, flat, down}
@attribute 'ca' real
@attribute 'thal' { fixed_defect, normal, reversable_defect}
@attribute 'class' { negative, positive}
@data
63,male,typ_angina,145,233,t,left_vent_hyper,150,no,2.3,down,0,fixed_defect,negative
37,male,non_anginal,130,250,f,normal,187,no,3.5,down,0,normal,negative
41,female,atyp_angina,130,204,f,left_vent_hyper,172,no,1.4,up,0,normal,negative
56,male,atyp_angina,120,236,f,normal,178,no,0.8,up,0,normal,negative
57,female,asympt,120,354,f,normal,163,yes,0.6,up,0,normal,negative
57,male,asympt,140,192,f,normal,148,no,0.4,flat,0,fixed_defect,negative
56,female,atyp_angina,140,294,f,left_vent_hyper,153,no,1.3,flat,0,normal,negative
44,male,atyp_angina,120,263,f,normal,173,no,0,up,0,reversable_defect,negative
52,male,non_anginal,172,199,t,normal,162,no,0.5,up,0,reversable_defect,negative

ここに私が書いたサンプルコードがあります:

arr=[]
arff_file = open("heart_train.arff")
count=0
for line in arff_file:
        count+=1
        #line=line.strip("\n")
        #line=line.split(',')
        if not (line.startswith("@")):
                if not (line.startswith("%")):
                        line=line.strip("\n")
                        line=line.split(',')
                        arr.append(line)



print(arr[1:30])

ただし、出力は予想とは大きく異なります。

[['37', 'male', 'non_anginal', '130', '250', 'f', 'normal', '187', 'no', '3.5', 'down', '0', 'normal', 'negative'], ['41', 'female', 'atyp_angina', '130', '204', 'f', 'left_vent_hyper', '172', 'no', '1.4', 'up', '0', 'normal', 'negative'], ['56', 'male', 'atyp_angina', '120', '236', 'f', 'normal', '178', 'no', '0.8', 'up', '0', 'normal', 'negative'], ['57', 'female', 'asympt', '120', '354', 'f', 'normal', '163', 'yes', '0.6', 'up', '0', 'normal', 'negative'], ['57', 'male', 'asympt', '140', '192', 'f', 'normal', '148', 'no', '0.4', 'flat', '0', 'fixed_defect', 'negative'], ['56', 'female', 'atyp_angina', '140', '294', 'f', 'left_vent_hyper', '153', 'no', '1.3', 'flat', '0', 'normal', 'negative'], ['44', 'male', 'atyp_angina', '120', '263', 'f', 'normal', '173', 'no', '0', 'up', '0', 'reversable_defect', 'negative'], ['52', 'male', 'non_anginal', '172', '199', 't', 'normal', '162', 'no', '0.5', 'up', '0', 'reversable_defect', 'negative'], ['57', 'male', 'non_anginal', '150', '168', 'f', 'normal', '174', 'no', '1.6', 'up', '0', 'normal', 'negative'], ['54', 'male', 'asympt', '140', '239', 'f', 'normal', '160', 'no', '1.2', 'up', '0', 'normal', 'negative'], ['48', 'female', 'non_anginal', '130', '275', 'f', 'normal', '139', 'no', '0.2', 'up', '0', 'normal', 'negative'], ['49', 'male', 'atyp_angina', '130', '266', 'f', 'normal', '171', 'no', '0.6', 'up', '0', 'normal', 'negative'], ['64', 'male', 'typ_angina', '110', '211', 'f', 'left_vent_hyper', '144', 'yes', '1.8', 'flat', '0', 'normal', 'negative'], ['58', 'female', 'typ_angina', '150', '283', 't', 'left_vent_hyper', '162', 'no', '1', 'up', '0', 'normal', 'negative'], ['50', 'female', 'non_anginal', '120', '219', 'f', 'normal', '158', 'no', '1.6', 'flat', '0', 'normal', 'negative'], ['58', 'female', 'non_anginal', '120', '340', 'f', 'normal', '172', 'no', '0', 'up', '0', 'normal', 'negative'], ['66', 'female', 'typ_angina', '150', '226', 'f', 'normal', '114', 'no', '2.6', 'down', '0', 'normal', 'negative'], ['43', 'male', 'asympt', '150', '247', 'f', 'normal', '171', 'no', '1.5', 'up', '0', 'normal', 'negative'], ['69', 'female', 'typ_angina', '140', '239', 'f', 'normal', '151', 'no', '1.8', 'up', '2', 'normal', 'negative'], ['59', 'male', 'asympt', '135', '234', 'f', 'normal', '161', 'no', '0.5', 'flat', '0', 'reversable_defect', 'negative'], ['44', 'male', 'non_anginal', '130', '233', 'f', 'normal', '179', 'yes', '0.4', 'up', '0', 'normal', 'negative'], ['42', 'male', 'asympt', '140', '226', 'f', 'normal', '178', 'no', '0', 'up', '0', 'normal', 'negative'], ['61', 'male', 'non_anginal', '150', '243', 't', 'normal', '137', 'yes', '1', 'flat', '0', 'normal', 'negative'], ['40', 'male', 'typ_angina', '140', '199', 'f', 'normal', '178', 'yes', '1.4', 'up', '0', 'reversable_defect', 'negative'], ['71', 'female', 'atyp_angina', '160', '302', 'f', 'normal', '162', 'no', '0.4', 'up', '2', 'normal', 'negative'], ['59', 'male', 'non_anginal', '150', '212', 't', 'normal', '157', 'no', '1.6', 'up', '0', 'normal', 'negative'], ['51', 'male', 'non_anginal', '110', '175', 'f', 'normal', '123', 'no', '0.6', 'up', '0', 'normal', 'negative'], ['65', 'female', 'non_anginal', '140', '417', 't', 'left_vent_hyper', '157', 'no', '0.8', 'up', '1', 'normal', 'negative'], ['53', 'male', 'non_anginal', '130', '197', 't', 'left_vent_hyper', '152', 'no', '1.2', 'down', '0', 'normal', 'negative']]

Arff ライブラリ (Weka から) によって作成された次のような出力を取得する方法を知っていますか? ここに画像の説明を入力

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1 に答える 1

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「外部ライブラリはありません」と言いますが、少なくとも自分のコードにカットアンドペーストできますか? arff モジュールのソース コードが役立つ場合があります(200 行、約 5.6 KB)。

編集:

この形式の参照が役立つ場合があります: http://weka.wikispaces.com/ARFF+%28stable+version%29

編集2:

楽しみのために、独自の .arrf パーサーを作成しました。これは WEKA コードとほぼ同じ長さですが、より読みやすいはずです。わずか 6 つの関数、ディスパッチ テーブル、および非常にモジュール化されたクラスです。クラス インスタンスを反復処理して、各データ行を名前付きタプルとして取得できます。

あなたの考えを見てください:

from collections import namedtuple
from keyword import iskeyword
import re

def NotDone(msg):
    raise NotImplemented(msg)

def nominal(spec):
    """
    Create an ARFF nominal (enumerated) data type
    """
    spec = spec.lstrip("{ \t").rstrip("} \t")
    good_values = set(val.strip() for val in spec.split(","))

    def fn(s):
        s = s.strip()
        if s in good_values:
            return s
        else:
            raise ValueError("'{}' is not a recognized value".format(s))

    # patch docstring
    fn.__name__ = "nominal"
    fn.__doc__ = """
    ARFF nominal (enumerated) data type

    Legal values are {}
    """.format(sorted(good_values))
    return fn

def numeric(s):
    """
    Convert string to int or float
    """
    try:
        return int(s)
    except ValueError:
        return float(s)

field_maker = {
    "date":       (lambda spec: NotDone("date data type not implemented")),
    "integer":    (lambda spec: int),
    "nominal":    (lambda spec: nominal(spec)),
    "numeric":    (lambda spec: numeric),
    "string":     (lambda spec: str),
    "real":       (lambda spec: float),
    "relational": (lambda spec: NotDone("relational data type not implemented")),
}

def file_lines(fname):
    # lazy file reader; ensures file is closed when done,
    # returns lines without trailing spaces or newline
    with open(fname) as inf:
        for line in inf:
            yield line.rstrip()

def no_data_yet(*items):
    raise ValueError("AarfRow not fully defined (haven't seen a @data directive yet)")

def make_field_name(s):
    """
    Mangle string to make it a valid Python identifier
    """
    s = s.lower()                               # force to lowercase
    s = "_".join(re.findall("[a-z0-9]+", s))    # strip all invalid chars; join what's left with "_"
    if iskeyword(s) or re.match("[0-9]", s):    # if the result is a keyword or starts with a digit
        s = "f_"+s                              #   make it a safe field name
    return s  

class ArffReader:
    line_types = ["blank", "comment", "relation", "attribute", "data"]

    def __init__(self, fname):
        # get input file
        self.fname = fname
        self.lines = file_lines(fname)

        # prepare to read file header
        self.relation = '(not specified)'
        self.data_names = []
        self.data_types = []
        self.dtype = no_data_yet

        # read file header
        line_tests = [
            (getattr(self, "line_is_{}".format(item)), getattr(self, "line_do_{}".format(item)))
            for item in self.__class__.line_types
        ]
        for line in self.lines:
            for is_, do in line_tests:
                if is_(line):
                    done = do(line)
                    break
            if done:
                break

        # use header fields to build data type (and make it print as requested)
        class ArffRow(namedtuple('ArffRow', self.data_names)):
            __slots__ = ()
            def __str__(self):
                items = (getattr(self, field) for field in self._fields)
                return "({})".format(", ".join(repr(it) for it in items))
        self.dtype = ArffRow

    #
    # figure out input-line type
    #

    def line_is_blank(self, line):
        return not line

    def line_is_comment(self, line):
        return line.lower().startswith('%')

    def line_is_relation(self, line):
        return line.lower().startswith('@relation')

    def line_is_attribute(self, line):
        return line.lower().startswith('@attribute')

    def line_is_data(self, line):
        return line.lower().startswith('@data')

    #    
    # handle input-line type
    #    

    def line_do_blank(self, line):
        pass

    def line_do_comment(self, line):
        pass

    def line_do_relation(self, line):
        self.relation = line[10:].strip()

    def line_do_attribute(self, line):
        m = re.match(
            "^@attribute"           #   line starts with '@attribute'
            "\s+"                   #
            "("                     # name is one of:
                "(?:'[^']+')"       #   ' string in single-quotes '
                "|(?:\"[^\"]+\")"   #   " string in double-quotes "
                "|(?:[^ \t'\"]+)"   #   single_word_string (no spaces)
            ")"                     #
            "\s+"                   #
            "("                     # type is one of:
                "(?:{[^}]+})"       #   { set, of, nominal, values }
                "|(?:\w+)"          #   datatype
            ")"                     #
            "\s*"                   #
            "("                     # spec string
                ".*"                #   anything to end of line
            ")$",                   #
            line, flags=re.I)       #   case-insensitive
        if m:
            name, type_, spec = m.groups()
            self.data_names.append(make_field_name(name))
            if type_[0] == '{':
                type_, spec = 'nominal', type_
            self.data_types.append(field_maker[type_](spec))
        else:
            raise ValueError("failed parsing attribute line '{}'".format(line))

    def line_do_data(self, line):
        return True  # flag end of header

    #
    # make the class iterable
    #

    def __iter__(self):
        return self

    def next(self):
        """
        Return one data row at a time
        """
        data = next(self.lines).split(',')
        return self.dtype(*(fn(dat) for fn,dat in zip(self.data_types, data)))

そしてそれはとして使用することができます

for row in ArffReader('mydata.arff'):
    print(row)

その結果、

(63.0, 'male', 'typ_angina', 145.0, 233.0, 't', 'left_vent_hyper', 150.0, 'no', 2.3, 'down', 0.0, 'fixed_defect', 'negative')
(37.0, 'male', 'non_anginal', 130.0, 250.0, 'f', 'normal', 187.0, 'no', 3.5, 'down', 0.0, 'normal', 'negative')
(41.0, 'female', 'atyp_angina', 130.0, 204.0, 'f', 'left_vent_hyper', 172.0, 'no', 1.4, 'up', 0.0, 'normal', 'negative')
(56.0, 'male', 'atyp_angina', 120.0, 236.0, 'f', 'normal', 178.0, 'no', 0.8, 'up', 0.0, 'normal', 'negative')
(57.0, 'female', 'asympt', 120.0, 354.0, 'f', 'normal', 163.0, 'yes', 0.6, 'up', 0.0, 'normal', 'negative')
(57.0, 'male', 'asympt', 140.0, 192.0, 'f', 'normal', 148.0, 'no', 0.4, 'flat', 0.0, 'fixed_defect', 'negative')
(56.0, 'female', 'atyp_angina', 140.0, 294.0, 'f', 'left_vent_hyper', 153.0, 'no', 1.3, 'flat', 0.0, 'normal', 'negative')
(44.0, 'male', 'atyp_angina', 120.0, 263.0, 'f', 'normal', 173.0, 'no', 0.0, 'up', 0.0, 'reversable_defect', 'negative')
(52.0, 'male', 'non_anginal', 172.0, 199.0, 't', 'normal', 162.0, 'no', 0.5, 'up', 0.0, 'reversable_defect', 'negative')

フィールドは名前でもアドレス指定できます。

for patient in ArffReader('mydata.arff'):
    print("{} year old {}".format(patient.age, patient.sex))

を与える

63.0 year old male
37.0 year old male
41.0 year old female
56.0 year old male
57.0 year old female
57.0 year old male
56.0 year old female
44.0 year old male
52.0 year old male

そして、あなたはファイル名を見ることができます

>>> print(repr(patient))
ArffRow(age=63.0, sex='male', cp='typ_angina', trestbps=145.0, chol=233.0, fbs='t', restecg='left_vent_hyper', thalach=150.0, exang='no', oldpeak=2.3, slope='down', ca=0.0, thal='fixed_defect', f_class='negative')

フィールド名は ARFF ヘッダーのとおりで、小文字が強制されます (「class」の場合、「f_」が先頭に追加されるのclassは Python のキーワードであるため、フィールド名として使用できないからです)。

于 2014-03-05T03:24:10.237 に答える