Question

这是我的代码：

Top_5 = []
with open (("winscorefile.txt"),"r") as Top5_File:
    for number in Top5_File:
        Top_5.append(number)
        Top_5.sort()
        Top_5.reverse()
        number_of_items = len(Top_5)
     while number_of_items > 5:
        Top_5.pop()
        number_of_items = len(Top_5)

    for data in Top_5:
        print(data)

我的文本文件看起来像（它是分数和用户名的集合）：

62 rob 
100 rob
56 ROB 
54 rob 
76 bor 
64 bor 
52 a 
44 p1 
54 p1 
46 p2 
74 p1 
52 p2 
66 p2 
76 p2 
38 p2 
60 p1 
58 p1

我的文件旨在输出前5个最高得分。它正在执行此操作，但仅输出最高的两位数字。我不知道为什么它忽略了100分。

Answer 1

您可以这样做

$ gradle clean test --console=plain -Dorg.gradle.java.home=/Library/Java/JavaVirtualMachines/jdk-10.0.2.jdk/Contents/Home
...
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.parboiled.transform.AsmUtils (file:/Users/bountin/.gradle/caches/modules-2/files-2.1/org.parboiled/parboiled-java/1.1.7/2298c64ce8ee8e2fb37e97e16d7be52f0c7cf61f/parboiled-java-1.1.7.jar) to method java.lang.ClassLoader.findLoadedClass(java.lang.String)
WARNING: Please consider reporting this to the maintainers of org.parboiled.transform.AsmUtils
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
...
- should test fine *** FAILED *** (2 seconds, 210 milliseconds)
  java.lang.IllegalArgumentException: Error while instantiating 'org.apache.spark.sql.hive.HiveSessionStateBuilder':
  at org.apache.spark.sql.SparkSession$.org$apache$spark$sql$SparkSession$$instantiateSessionState(SparkSession.scala:1075)
  at org.apache.spark.sql.SparkSession$$anonfun$sessionState$2.apply(SparkSession.scala:142)
  at org.apache.spark.sql.SparkSession$$anonfun$sessionState$2.apply(SparkSession.scala:141)
  at scala.Option.getOrElse(Option.scala:121)
  at org.apache.spark.sql.SparkSession.sessionState$lzycompute(SparkSession.scala:141)
  at org.apache.spark.sql.SparkSession.sessionState(SparkSession.scala:138)
  at org.apache.spark.sql.Dataset.<init>(Dataset.scala:171)
  at org.apache.spark.sql.Dataset$.apply(Dataset.scala:62)
  at org.apache.spark.sql.SparkSession.createDataset(SparkSession.scala:471)
  at org.apache.spark.sql.SQLContext.createDataset(SQLContext.scala:377)
  ...
  Cause: java.lang.ClassNotFoundException: java.lang.NoClassDefFoundError: org/apache/hadoop/hive/ql/session/SessionState when creating Hive client using classpath: file:/Users/bountin/classpath-gradle-test-failures/build/classes/java/test, file:/Users/bountin/classpath-gradle-test-failures/build/classes/scala/test/
Please make sure that jars for your version of hive and hadoop are included in the paths passed to spark.sql.hive.metastore.jars.
...

Answer 2

您可以在空间上分割单行并将第一部分转换为整数。

然后，您可以将数字和此人作为元组添加到列表中：

Top_5 = []
Top5_File = """
    62 rob
    100 rob
    56 ROB
    54 rob
    76 bor
    64 bor
    52 a
    44 p1
    54 p1
    46 p2
    74 p1
    52 p2
    66 p2
    76 p2
    38 p2
    60 p1
    58 p1
""".strip().split("\n")
for number in Top5_File:
    number, person = number.strip().split(" ")
    Top_5.append((int(number), person))
# sort only once, outside the loop!
Top_5.sort(reverse=True)
number_of_items = len(Top_5)
while number_of_items > 5:
    Top_5.pop()
    number_of_items = len(Top_5)

for data in Top_5:
    print(data)

输出：

(100, 'rob')
(76, 'bor')
(76, 'p2')
(74, 'p1')
(66, 'p2')

如果您不想使用元组，可以使用：

for number in Top5_File:
    Top_5.append(number.strip())
Top_5.sort(key=lambda x: int(x.split(" ")[0]), reverse=True)
number_of_items = len(Top_5)
while number_of_items > 5:
    Top_5.pop()
    number_of_items = len(Top_5)

for data in Top_5:
    print(data)

输出：

100 rob
76 bor
76 p2
74 p1
66 p2

Answer 3

打开文件后，您需要.read（）或.readlines（）

Top_5 = []
with open (("winscorefile.txt"),"r") as Top5_File:
    for line in Top5_File.readlines():
        line = line.strip()    # remove white spaces
        number, txt = line.split(' ')   # txt is useless here
        Top_5.append(int(number))
    Top_5.sort()
    Top_5.reverse()
    for data in Top_5[:5]:   # this grabs the first 5 elements including 0,1,2,3,4 elements
        print(data)

编辑* 如果输入为：76 p2，则line.split（''）应该返回两个对象组成的数组（有一个空格），因此看起来您的数据文件具有多个空格作为分隔符。试试这个：

for line in Top5_File.readlines():
    line = line.strip()    # remove white spaces
    if ' ' in line:        # check to make sure theres a space in there
        splitted = line.split(' ')
        number = splitted[0]
        Top_5.append(int(number))

Answer 4

 for number in Top5_File:
        Top_5.append(number)
        Top_5.sort()
        Top_5.reverse()
        number_of_items = len(Top_5)

基本上number是您的数据行，即第一个是62 rob

要提取此内容，您必须执行以下操作：

number.split(" ")会将行拆分为包含以下内容的数组：["62", "rob"]然后，您必须解析可以使用arr[0] = int(arr[0]进行操作的int，现在您的行将采用以下形式：< / p>

arr = [62, "rob"]现在，我建议将(score, name)的元组添加到您的Top_5数组中，如下所示： Top_5.append((arr[0], arr[1]))

然后，您将必须更改sort and reverse，因为您将存储元组，而不仅仅是数组Top_5中的字符串。我相信可以使用key参数和lambda来完成。它看起来像： sort(key = lambda x: x[0])，对于反向操作也可以这样做。

我希望这会有所帮助！

为什么我的代码无法从txt文件中读取3位数字？

4 个答案: