why a[0][0].__mul__(a[0][0]) where a is np.array, gives 'missing 1 required positional argument'?
The following code:
--{--cut here--
#Purpose:
# Demonstrate class with __add__ and __mult__ methods
# to demonstrate shortestPath calculations.
#OriginalSource:
# ./shortestPath.py
#References:
# [1]
http://www.marinamele.com/2014/04/modifying-add-method-of-python-class.html
# [2]
https://docs.scipy.org/doc/numpy/reference/c-api.types-and-structures.html#c...
# [3]
https://www.abebooks.com/book-search/title/graphs-networks/author/carre-bern...
# Table 3.1, path algebra P2.
# [4] https://docs.python.org/3/library/abc.html
###########################################
import numpy as np
from abc import ABCMeta, abstractmethod
class PathAbstract(metaclass=ABCMeta):
@abstractmethod
def __repr__(self):
pass
@abstractmethod
def __add__(self, other):
pass
@abstractmethod
def __radd__(self, other):
pass
@abstractmethod
def __mul__(self, other):
pass
@abstractmethod
def __rmul__(self, other):
pass
class ShortestNull(PathAbstract):
'''Null object in ShortestPath algebra[3]'''
def __str__(self):
return "<0>"
def __repr__(self):
return self.__str__()
def __addreal__(self, other):
return other
def __add__(self, other):
return other
def __radd__(self, other):
return other
def __mulreal__(self, other):
return self
def __mul__(self, other):
return self
def __rmul__(self, other):
return self
class ShortestUnit(PathAbstract):
'''Unit object in ShortestPath algebra[3]'''
def __str__(self):
return "<1>"
def __repr__(self):
return self.__str__()
def __addreal__(self, other):
return self
def __add__(self, other):
return self
def __radd__(self, other):
return self
def __mulreal__(self, other):
return other
def __mul__(self, other):
return other
def __rmul__(self, other):
return other
class ShortestPath(PathAbstract):
def __init__(self, distance):
self.distance = distance
def __str__(self):
return "{0:4.1f}".format(self.distance)
def __repr__(self):
return self.__str__()
def __addreal__(self, other):
#paths composed of following shortest of self path or other path.
min_dist=min(self.distance,other.distance)
return ShortestPath(min_dist)
def __add__(self, other):
#paths composed of following shortest of self path or other path.
if(other == 0):
n=ShortestNull()
return n.__addreal__(self)
else:
return other.__addreal__(self)
def __radd__(self, other):
return self.__add__(other)
def __mulreal__(self, other):
#path composed of self path followed by other path.
min_dist=self.distance+other.distance
return ShortestPath(min_dist)
def __mul__(self, other):
return other.__mulreal__(self)
def __rmul__(self, other):
return other.__mulreal__(self)
d0=ShortestNull()
d1=ShortestUnit()
d2=ShortestPath(3)
d3=ShortestPath(6)
print(' d0=',d0,' d1=',d1,' d2=',d2,' d3=',d3)
print(' type(d0)=',type(d0).__name__)
d4=d0+d2+d3
print('d4=',d4)
d5=d2*d3
print('d5=',d5)
d6=d0*d2
print('d6=',d6)
d7=d1*d2
print('d7=',d7)
d8=d2*d0
print('d8=',d8)
d9=d2*d1
print('d9=',d9)
a=np.array([[ShortestNull,ShortestPath(12)],[ShortestPath(12),ShortestNull()]],dtype=object)
print('a=',a,sep='\n')
print('a[0]=',a[0],sep='\n')
print('a[0][0]=',a[0][0],sep='\n')
#a00mul=a[0][0]*a[0][0]
a00mul=a[0][0].__mul__(a[0][0])
print('a00mul=',a00mul,sep='\n')
#at=a.transpose()
#print('at=',at,sep='\n')
#aat=a.dot(at)
print('aat=',aat,sep='\n')
#mp=np.matmul(a,at)#this gives error about Object arrays not supported.
#print('mp=',mp)
--}--cut here--
When run by make, gives this result:
--{--cut here--
make -k
python3 shortestPathABC.py
d0= <0> d1= <1> d2= 3.0 d3= 6.0
type(d0)= ShortestNull
d4= 3.0
d5= 9.0
d6= <0>
d7= 3.0
d8= <0>
d9= 3.0
a=
[[
On Tue, Jun 27, 2017 at 2:54 AM, Larry Evans
a= [[
12.0] [12.0 <0>]] a[0]= [ 12.0] a[0][0]= Traceback (most recent call last): File "shortestPathABC.py", line 123, in <module> a00mul=a[0][0].__mul__(a[0][0]) TypeError: __mul__() missing 1 required positional argument: 'other' Makefile:7: recipe for target 'all' failed make: *** [all] Error 1 --}--cut here-- I don't understand why. Apparently, a[0][0] is not a ShortestNull because otherwise, the .__mul__ would have the positional argument, 'other' equal to a[0][0].
What am I missing?
a=np.array([[ShortestNull,ShortestPath(12)],[ShortestPath( 12),ShortestNull()]],dtype=object)
You didn't instantiate ShortestNull but passed the class object instead. -- Robert Kern
On Tue, 2017-06-27 at 04:54 -0500, Larry Evans wrote:
The following code:
--{--cut here-- #Purpose: # Demonstrate class with __add__ and __mult__ methods # to demonstrate shortestPath calculations. #OriginalSource: # ./shortestPath.py #References: # [1] http://www.marinamele.com/2014/04/modifying-add-method-of-python-clas s.html # [2] https://docs.scipy.org/doc/numpy/reference/c-api.types-and-structures .html#c.PyArray_Descr # [3] https://www.abebooks.com/book-search/title/graphs-networks/author/car re-bernard/ # Table 3.1, path algebra P2. # [4] https://docs.python.org/3/library/abc.html ########################################### import numpy as np from abc import ABCMeta, abstractmethod class PathAbstract(metaclass=ABCMeta): @abstractmethod def __repr__(self): pass @abstractmethod def __add__(self, other): pass @abstractmethod def __radd__(self, other): pass @abstractmethod def __mul__(self, other): pass @abstractmethod def __rmul__(self, other): pass
class ShortestNull(PathAbstract): '''Null object in ShortestPath algebra[3]''' def __str__(self): return "<0>" def __repr__(self): return self.__str__() def __addreal__(self, other): return other def __add__(self, other): return other def __radd__(self, other): return other def __mulreal__(self, other): return self def __mul__(self, other): return self def __rmul__(self, other): return self
class ShortestUnit(PathAbstract): '''Unit object in ShortestPath algebra[3]''' def __str__(self): return "<1>" def __repr__(self): return self.__str__() def __addreal__(self, other): return self def __add__(self, other): return self def __radd__(self, other): return self def __mulreal__(self, other): return other def __mul__(self, other): return other def __rmul__(self, other): return other
class ShortestPath(PathAbstract): def __init__(self, distance): self.distance = distance def __str__(self): return "{0:4.1f}".format(self.distance) def __repr__(self): return self.__str__() def __addreal__(self, other): #paths composed of following shortest of self path or other path. min_dist=min(self.distance,other.distance) return ShortestPath(min_dist) def __add__(self, other): #paths composed of following shortest of self path or other path. if(other == 0): n=ShortestNull() return n.__addreal__(self) else: return other.__addreal__(self) def __radd__(self, other): return self.__add__(other) def __mulreal__(self, other): #path composed of self path followed by other path. min_dist=self.distance+other.distance return ShortestPath(min_dist) def __mul__(self, other): return other.__mulreal__(self) def __rmul__(self, other): return other.__mulreal__(self)
d0=ShortestNull() d1=ShortestUnit() d2=ShortestPath(3) d3=ShortestPath(6) print(' d0=',d0,' d1=',d1,' d2=',d2,' d3=',d3) print(' type(d0)=',type(d0).__name__) d4=d0+d2+d3 print('d4=',d4) d5=d2*d3 print('d5=',d5) d6=d0*d2 print('d6=',d6) d7=d1*d2 print('d7=',d7) d8=d2*d0 print('d8=',d8) d9=d2*d1 print('d9=',d9) a=np.array([[ShortestNull,ShortestPath(12)],[ShortestPath(12),Shortes tNull()]],dtype=object) print('a=',a,sep='\n') print('a[0]=',a[0],sep='\n') print('a[0][0]=',a[0][0],sep='\n') #a00mul=a[0][0]*a[0][0] a00mul=a[0][0].__mul__(a[0][0]) print('a00mul=',a00mul,sep='\n') #at=a.transpose() #print('at=',at,sep='\n') #aat=a.dot(at) print('aat=',aat,sep='\n') #mp=np.matmul(a,at)#this gives error about Object arrays not supported. #print('mp=',mp) --}--cut here--
When run by make, gives this result:
--{--cut here-- make -k python3 shortestPathABC.py d0= <0> d1= <1> d2= 3.0 d3= 6.0 type(d0)= ShortestNull d4= 3.0 d5= 9.0 d6= <0> d7= 3.0 d8= <0> d9= 3.0 a= [[
12.0] [12.0 <0>]] a[0]= [ 12.0] a[0][0]= Traceback (most recent call last): File "shortestPathABC.py", line 123, in <module> a00mul=a[0][0].__mul__(a[0][0]) TypeError: __mul__() missing 1 required positional argument: 'other' Makefile:7: recipe for target 'all' failed make: *** [all] Error 1 --}--cut here-- I don't understand why. Apparently, a[0][0] is not a ShortestNull because otherwise, the .__mul__ would have the positional argument, 'other' equal to a[0][0].
I don't think debugging support really suits the list, but.... how
about you see why in your result:
[[
What am I missing?
TIA.
-regards, Larry _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@python.org https://mail.python.org/mailman/listinfo/numpy-discussion
participants (3)
-
Larry Evans
-
Robert Kern
-
Sebastian Berg