I have a dataframe defined earlier by this format
vars()['df_zscore_out1']=
I'm trying to access this dataframe inside a function and call this func()
def func():
print(vars()['df_zscore_out1'])
func()
But got
KeyError: 'df_zscore_out1'
I tried passing it in the argument and it works
def func(df):
print(df)
func(vars()['df_zscore_out1'])
Can anyone help to explain this? Thanks!
From the docs:
Without an argument, vars() acts like locals(). Note, the locals dictionary is only useful for reads since updates to the locals dictionary are ignored.
Since it isn't a local, it isn't accessible.
Just pass it in as an argument though. If a function needs data, parameters are how that data should be supplied unless you really need a more flexible solution.
When vars() is called without any arguments, it's equivalent to locals(), which only returns local variables. At the module level, locals() is equivalent to globals().
So, when you call vars() outside of the function, you are essentially calling globals() and getting a list of global variables. When you call vars() inside func(), you are essentially calling locals() and getting the (empty) list of local variables in func().
In order for vars() to be meaningful in this scenario, you'd need to pass the specific object you are trying to store variables in (i.e. a module, class, or instance).
Alternatively, you could call globals() directly instead of vars().
Sources:
global being referenced. Edited.
vars()acts likelocals()."vars()['df_zscore_out1']=" don't do this. Just stop dynamically creating variables. The problem is that in the global scope,vars()returnsglobals(), and in a local scope, it returnslocals(). But you shouldn't be using any of these things, it's a bad design