如何在终端中执行main方法？

Question

我有一个 Python 程序，其中包含类定义、方法定义，最后还有一个调用这些方法和类的主方法。当我在终端中运行该程序时，它没有输出任何内容，也没有错误消息。我应该改变程序的编写方式吗？

主要方法在底部。

import re
import random

class node:
    def __init__(self, parent, daughters, edge):
        self.parent = parent
        self.daughters = daughters
        self.edge = edge
        trie.append(self)
        self.index = len(trie) - 1

def BruteForcePatternMatching(text, patterns):
    indices = []
    for pattern in patterns:
        pattern = re.compile(pattern)
        indices += pattern.finditer(text)
    return indices

def TrieConstruction(patterns, trie):
    trie.append(node(0, [], 0))
    for pattern in patterns:
        currentNode = trie[0]
        for base in pattern:
            for daughter in currentNode.daughters:
                if base == daughter.edge:
                    currentNode = daughter
                    break
            else:
                trie.append(node(currentNode, [], base))
                currentNode = trie[-1]

def PrefixTrieMatching(text, trie):
    v = trie[0]
    for index, base in enumerate(text):
        if v.daughters == []:
            pattern_out = []
            climb(v.index)
            return ''.join(pattern_out)
        else:
            for daughter in v.daughters:
                if base == daughter.edge:
                    v = daughter
                    break
            else:
                print('No matches found.')
                return

def climb(index):
    if index == 0:
        return
    else:
        pattern_out.append(node.edge)
        climb(trie[index].parent)

def TrieMatching(text, trie):
    while not text == []:
        PrefixTrieMatching(text, trie)
        text = text[:-1]

def SuffixTrieConstruction(text):
    trie = [node(0, [1], 0), node(0, [], len(text) + 1)] #we use normal nodes, but if they are leaves, we give them integers for indices

    for index in range(len(text)): 
        start = len(text) - index
        slide = text[start:-1]
        currentNode = trie[0]

        for symbol in slide:
            for daughter in currentNode.daughters:
                if symbol == daughter.edge:
                    currentNode = daughter
                    break
            else:
                trie.append(node(currentNode.index, [], symbol)) 
                currentNode = trie[-1]

            if symbol == slide[-1]:
                trie.append(node(currentNode.index, [], start))

    return trie

def SuffixTreeConstruction(trie):
    for node in trie:
        if len(node.daughters) == 1:
            node.edge = node.edge + trie[node.daughter[0]].edge
            trie[node.daughters[0]].parent = node.index
            node.daughters = trie[currentNode.daughters[0]].daughters
            del trie[node.daughter[0]]

    for node in trie:
        for daughter in node.daughters:
            print('(%d, %d, %s') % (node.index, daughter, node.edge)


def main():

    print('First, we open a file of DNA sequences and generate a random DNA string of length 3000, representative of the reference genome.')

    patterns = list(open('patterns'))
    text = ''
    for count in range(3000):
        text += choice('ACTG')

    print('We will first check for matches using the Brute Force matching method, which scans the text for matches of each pattern.')
    BruteForcePatternMatching(text, patterns)
    print('It returns the indices in the text where matches occur.')
    print('Next, we generate a trie with the patterns, and then run the text over the trie to search for matches.')
    trie = []
    TrieConstruction(patterns, trie)
    TrieMatching(text, trie)
    print('It returns all matched patterns.')
    print('Finally, we can construct a suffix tree from the text. This is the concatenation of all non-branching nodes into a single node.')
    SuffixTreeConstruction(SuffixTrieConstruction(text))
    print('It returns the adjacency list - (parent, daughter, edge).')

Answer 1

假设您的代码保存在myfile.py.

正如其他所述，您可以添加：

if __name__ == "__main__":
    main()

在文件末尾并使用 运行它python myfile.py。

但是，如果由于某些不明原因，您无法修改文件的内容，您仍然可以通过以下方式实现此目的：

python -c "import myfile; myfile.main()"

从命令行。（只要您从包含的目录运行它myfile）