The following is a class from a search engine program that I'm working on (via a text book). I'm attempting to modify the following code so that it will count the number of occurrences a user's entry has from a source. My initial attempts was to create a new method that would count the number of entries in the dictionary self._wordAt and return that amount as an integer value via the total, but I keep getting the total amount of words that self._wordAt holds.

So my question is, what is the proper syntax I should be following that would let me count the amount of occurrences from an entry?

I'm under the impression that I'd need to implement an additional dict() that would keep track of the amount of occurrences, but I'm not sure how to implement that either.

class TextIndex:
  """Manage an index of words occurring in a work of text."""

  def __init__(self, contents, sourceLabel):
    """Construct a new index for the given document.

    contents         a single string representing the complete contents
    sourceLabel      a string which identifies the source of the contents
    self._lines = contents.split('\n')
    self._label= sourceLabel

    # Now build a dictionary on the apparent words of the file.
    # Each word is mapped to an ordered list of line numbers at which that word occurs
    self._wordAt = {}
    for linenum in range(len(self._lines)):
      words = self._lines[linenum].split()
      for w in words:
        w = ourStrip(w)
        if w:                                     # not reduced to empty string
          if w not in self._wordAt:               # this is first occurrence of the word
            self._wordAt[w] = [ linenum ]
          elif self._wordAt[w][-1] != linenum:    # occurring on a new line for this word

  def getLabel(self):
    """Return the string which serves as a layer for this document."""
    return self._label

  def getWords(self):
    """Return an unordered list of words appearing in this document."""
    return self._wordAt.keys()
  def getContext(self, word, maxOccur=10):
    """Return a string demonstrating occurrences of the word in context.

    Will show up to maxOccur distinct occurrences (default 10)
    word = ourStrip(word)                         # clean query term
    output = []                                   # build list of lines to output
    if word in self._wordAt:
      occurrences = self._wordAt[word]            # list of line numbers
      for lineNum in occurrences[ : maxOccur]:    # limit the number of reported results
        startContext = max(lineNum - 1, 0)        # typically the previous line
        stopContext = min(lineNum + 2, len(self._lines))
        output.append('-' * 40)
        output.extend(self._lines[startContext : stopContext])
    return '\n'.join(output)

First, my personal opinion is that "in" is more straight forward than "-1"

#elif self._wordAt[w][-1] != linenum: # occurring on a new line for this word
elif linenum not in self._wordAt[w]

To get the number of times it occurs, I would suggest that you print 10 items of the dictionary. This should give you an idea of how to get the number of occurrences for each word; {"the":1, 3, 7} = "the" occurs in 3 lines.

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