Ggtcf

I am trying to write my first function using numba jit, I have a pandas dataframe that I need to iterate through and find the root mean square for each 350 points, since the for loop of python is quite slow I decided to try numba jit, the code is:

@jit(nopython=True)
def find_rms(data, length):
 res = []
 for i in range(length, len(data)):
 interval = np.array(data[i-length:i])
 interval =np.power(interval, 2)
 sum = interval.sum()
 resI = sum/length
 resI = np.sqrt(res)
 res.appennd(resI)
 return res

mydf = np.array(df.iloc[:]['c0'], dtype=np.float64)
df.iloc[350:]['rms'] = find_rms(mydf, 350)

I read somewhere thad I need to specify datatypes, therefore I wrote "dtype = np.float64" but I still get the error as:

---------------------------------------------------------------------------
TypingError Traceback (most recent call last)
<ipython-input-39-4d388f72efdc> in <module>
----> 1 df.iloc[350:]['rms'] = find_rms(mydf, 350.0)

c:users1appdatalocalprogramspythonpython35libsite-packagesnumbadispatcher.py in _compile_for_args(self, *args, **kws)
 346 e.patch_message(msg)
 347 
--> 348 error_rewrite(e, 'typing')
 349 except errors.UnsupportedError as e:
 350 # Something unsupported is present in the user code, add help info

c:users1appdatalocalprogramspythonpython35libsite-packagesnumbadispatcher.py in error_rewrite(e, issue_type)
 313 raise e
 314 else:
--> 315 reraise(type(e), e, None)
 316 
 317 argtypes = []

c:users1appdatalocalprogramspythonpython35libsite-packagesnumbasix.py in reraise(tp, value, tb)
 656 value = tp()
 657 if value.__traceback__ is not tb:
--> 658 raise value.with_traceback(tb)
 659 raise value
 660 

TypingError: Failed in nopython mode pipeline (step: nopython frontend)
Invalid use of Function(<built-in function array>) with argument(s) of type(s): (array(float64, 1d, C))
 * parameterized
In definition 0:
 TypingError: array(float64, 1d, C) not allowed in a homogeneous sequence
 raised from c:users1appdatalocalprogramspythonpython35libsite-packagesnumbatypingnpydecl.py:463
In definition 1:
 TypingError: array(float64, 1d, C) not allowed in a homogeneous sequence
 raised from c:users1appdatalocalprogramspythonpython35libsite-packagesnumbatypingnpydecl.py:463
This error is usually caused by passing an argument of a type that is unsupported by the named function.
[1] During: resolving callee type: Function(<built-in function array>)
[2] During: typing of call at <ipython-input-34-edd252715b2d> (5)


File "<ipython-input-34-edd252715b2d>", line 5:
def find_rms(data, length):
 <source elided>
 for i in range(length, len(data)):
 interval = np.array(data[i-length:i])
 ^

This is not usually a problem with Numba itself but instead often caused by
the use of unsupported features or an issue in resolving types.

To see Python/NumPy features supported by the latest release of Numba visit:
http://numba.pydata.org/numba-doc/dev/reference/pysupported.html
and
http://numba.pydata.org/numba-doc/dev/reference/numpysupported.html

For more information about typing errors and how to debug them visit:
http://numba.pydata.org/numba-doc/latest/user/troubleshoot.html#my-code-doesn-t-compile

If you think your code should work with Numba, please report the error message
and traceback, along with a minimal reproducer at:
https://github.com/numba/numba/issues/new

Does anybody know what the problem is?