Regarding dir() - python
Initially I was trying to find dir(re) but realized I had quotes.
Edit for clarity:
Wouldn't "re" be a string? So dir("re") == dir(string)? The output isn't the same. That is essentially what I am wondering.
Edit for comments:
I might misunderstand but doesn't dir return a list of all the functions within the module? Also when I call dir on "re" it gives me a list of functions. No error is returned.
edit2: yes dir. Been switching between a ruby and python project and for some reason I had def on the brain. sorry xD
I think what you need is a clarification on what dir does.
dir is a Python built-in function that does either one of two things, depending on whether an argument is supplied or not:
Without an argument, it returns a list of the names in the current scope. These names are represented as strings.
With an argument, it returns a list of the attributes and methods that belong to that argument. Once again, it will be a list of strings.
Below is a demonstration of the first action:
>>> num = 1 # Just to demonstrate
>>> dir()
['__builtins__', '__doc__', '__name__', '__package__', 'num']
>>>
And here is a demonstration of the second:
>>> dir(str)
['__add__', '__class__', '__contains__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__getslice__', '__gt__', '__hash__', '__init__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '_formatter_field_name_split', '_formatter_parser', 'capitalize', 'center', 'count', 'decode', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'index', 'isalnum', 'isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
>>>
Moreover, if its argument is a Python module, then dir will list the names contained in that module:
>>> import sys
>>> dir(sys)
['__displayhook__', '__doc__', '__excepthook__', '__name__', '__package__', '__stderr__', '__stdin__', '__stdout__', '_clear_type_cache', '_current_frames', '_getframe', '_mercurial', 'api_version', 'argv', 'builtin_module_names', 'byteorder', 'call_tracing', 'callstats', 'copyright', 'displayhook', 'dllhandle', 'dont_write_bytecode', 'exc_clear', 'exc_info', 'exc_type', 'excepthook', 'exec_prefix', 'executable', 'exit', 'flags', 'float_info', 'float_repr_style', 'getcheckinterval', 'getdefaultencoding', 'getfilesystemencoding', 'getprofile', 'getrecursionlimit',
'getrefcount', 'getsizeof', 'gettrace', 'getwindowsversion', 'hexversion', 'long_info', 'maxint', 'maxsize', 'maxunicode', 'meta_path', 'modules', 'path', 'path_hooks', 'path_importer_cache', 'platform', 'prefix', 'ps1', 'ps2', 'py3kwarning', 'setcheckinterval', 'setprofile', 'setrecursionlimit', 'settrace', 'stderr', 'stdin', 'stdout', 'subversion', 'version', 'version_info',
'warnoptions', 'winver']
>>>
Now, you said in your question that the output of dir("re") was not equal to dir(string). There are a few things I would like to say about this:
If string is a string literal, as in dir("string"), then it should work:
>>> dir("re") == dir("string")
True
>>>
If "re" is actually the re module, then the behavior you are seeing is expected since the module is not a string.
If you were expecting dir("re") to list the names contained in the re module, then you are mistaken. You cannot reference the module with a string. Instead, you have to explicitly import it first:
>>> dir("re") # The output is the same as doing dir(str)
['__add__', '__class__', '__contains__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__getslice__', '__gt__', '__hash__', '__init__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '_formatter_field_name_split', '_formatter_parser', 'capitalize', 'center', 'count', 'decode', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'index', 'isalnum', 'isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
>>>
>>> import re
>>> dir(re) # The output is for the re module, not str
['DEBUG', 'DOTALL', 'I', 'IGNORECASE', 'L', 'LOCALE', 'M', 'MULTILINE', 'S', 'Scanner', 'T', 'TEMPLATE', 'U', 'UNICODE', 'VERBOSE', 'X', '_MAXCACHE', '__all__', '__builtins__', '__doc__', '__file__', '__name__', '__package__', '__version__', '_alphanum', '_cache', '_cache_repl', '_compile', '_compile_repl', '_expand', '_pattern_type', '_pickle', '_subx', 'compile', 'copy_reg', 'error', 'escape', 'findall', 'finditer', 'match', 'purge', 'search', 'split', 'sre_compile', 'sre_parse', 'sub', 'subn', 'sys', 'template']
>>>
Related
Code executing if statement even though criteria not matched
I am using Telethon to listen to new messages in a Telegram channel. It receives messages ok but when I include an if statement to run if the new message contains specific text, the statement executes each time a new message is received even though the text is not in the message. I'm new to this and can't find an answer, so can anyone see what I'm doing wrong? from telethon import TelegramClient, events, sync #client.on(events.NewMessage(chats=chat_id)) async def newMessageListener(event): new_message = event.message.message chat_id = event.chat_id print(chat_id) print(new_message) if "rain" in new_message: do_stuff with client: client.run_until_disconnected() This is the result of dir(new_message) (formatted for better readability): dir(new_message) [ '__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isascii', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill' ]
Why did my_dict['key3'][0].upper() worked whereas my_dict['key3'][0].reverse() didnt work [duplicate]
This question already has answers here:
How do I reverse a string in Python?
(19 answers)
Closed 2 years ago.
Why did my_dict['key3'][0].upper() worked whereas my_dict['key3'][0].reverse() didnt work showing error as:
AttributeError Traceback (most recent call last)
<ipython-input-8-1cf579a91af7> in <module>
----> 1 my_dict['key3'][0].reverse()
AttributeError: 'str' object has no attribute 'reverse'
i have assigned my_dict as:
my_dict={'key1':123,'key2':[12,23,33],'key3':['item0','item1','item2']}
As the error says, there's no such method called reverse for str in Python. You can simply do: my_dict['key3'][0][::-1]
Simply because str has no reverse attribute as stated in the error. If you want to reverse a str object in Python, use this: my_string [::-1] Please read the error and search it on your web browser before coming here.
Strings do not have an attribute called .reverse(). A useful trick in python to be able to inspect what attributes/methods are available to you is the dir function:
>>> dir('my string')
['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isascii', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
You will notice no such reverse attribute. You can accomplish what you're after with the built-in reversed function or with slicing:
>>> ''.join(reversed('my string'))
'gnirts ym'
>>> 'my string'[::-1]
'gnirts ym'
I receive this error 'str' object has no attribute 'text' when I try to run the following code
I had removed .text and had just written peter_pan.split() but I was not sure whether the output was correct. import requests from nltk import FreqDist url = "https://www.gutenberg.org/files/16/16-0.txt" peter_pan = requests.get(url).text peter_pan_words = peter_pan.text.split() word_frequency = FreqDist(peter_pan_words) freq = word_frequency.most_common(3)[2][1] print(freq)
Where you are doing: peter_pan = requests.get(url).text The text that you are using is a method of the response object that is returned by requests.get. This method returns a string (containing the contents of the page). All this is fine. However, you are then doing: peter_pan_words = peter_pan.text.split() This time what you are trying to do is access the text method of a str object, but a str does not have any method called text. If you do print(dir(peter_pan)), you will see the attributes (methods/properties) that are available for you to access. You should see something similar to: ['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill'] You will see that text is not one of them (which is why you are getting the error), but you will also see that split is there -- and in fact all you need to do is to invoke split directly: peter_pan_words = peter_pan.split()
This part of your code: peter_pan = requests.get(url).text When you call .text, you are converting the object into a string. So, since it's now a string, you cannot call .text on it again. Simply change: peter_pan_words = peter_pan.text.split() to peter_pan_words = peter_pan.split()
How to get list of variables from a script?
I am having trouble getting a list of all variables in a file, and I have tried all methods that I can find, but there isn't a way that worked for me. dir() would return this:
['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isascii', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
While working on this, I also had trouble importing a file from a variable containing the file name. I have tried importlib.import_module(filename), with open(filename, 'r') as infile: needed_file = infile.read(), and __import__() was deprecated, in the end, I'm just using with open().
Back to my first problem, I have tried using getattr(), however I got the same results as with dir(). These are what I have tried:
named_objects = dir(self.filedat)
print(named_objects)
attrs = [attr for attr in dir(self.filename) if not attr.startswith('__')]
file_objects = [getattr(self.filedat, attr) for attr in attrs]
named_objects = []
for attr in file_objects:
if isfunction(attr):
named_objects.append(attr.__name__)
elif not isfunction(attr) and not isclass(attr) and not ismodule(attr) and not ismethod(attr):
named_objects.append(attr.__name__)
print(file_objects)
I have also tried many variations of those, and none of which have succeeded.
Edit:
I am trying to get a list of all manually defined variables in said file.
python global variable __name__ (a newbie question)
What are the following names when I first start my python shell? They do not look like functions from __builtins__: >>> dir(__name__) ['__add__', '__class__', '__contains__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__getslice__', '__gt__', '__hash__', '__init__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '_formatter_field_name_split', '_formatter_parser', 'capitalize', 'center', 'count', 'decode', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'index', 'isalnum', 'isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']
__name__ is a string and those a string methods. It's the name of the module or '__main__' on the toplevel. Hence this idiom appears often: if __name__ == '__main__': # this file was called directly, not imported main()
dir(__name__) shows the attributes of __name__, and since __name__ is a string, it shows the attributes of the str class. Most of the listed attributes are methods. You can get more information using help(): >>> help(str.index) Help on method_descriptor: index(...) S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found.