python：TypeError：+不支持的操作数类型：'numpy.ndarray'和'str'

Question

I want to build a model data using this code :

def modeldata(filename, ratingMatrix):
result={}
itemmatrix = matrixconvert(ratingMatrix)
current = 0
total = len(itemmatrix)

for item in itemmatrix:
    current+=1
    if current%100--0: print ("%d / %d" % (current,total))

    result[item] = neighbor
    #print result

with open(filename+".csv", "wb") as f:
    pickle.dump(result, f)

filename variable is a data result from clustering process that contains userid, itemid, and rating, `then ratingMatrix is a dictionary which contains key (user), subkey(item) and rating

10 dict 1 {'255': 3.0}

. Neighbor contains a similarity data.

0 tuple 2 (1.0, '9790')

I want to build a model data using those things above, I run the function with this code

modeldata(filename, ratingMatrix)

but, I get this error :

1 / 306
.
.
304 / 306
305 / 306
306 / 306
Traceback (most recent call last):

  File "<ipython-input-29-5af8931a8f1e>", line 1, in <module>
    modeldata(filename, ratingMatrix)

  File "<ipython-input-28-220883448026>", line 14, in modeldata
    with open(filename+".txt", "wb") as f:

TypeError: unsupported operand type(s) for +: 'numpy.ndarray' and 'str'

Do you have any idea what's wrong with this code ? where is the error from, and how can I make it work?

Thank you for your help....

Answer 1

The error you getting is within the modeldata function and more specifically the opening statement for writing to a file. The error is stating that you can't add using the "+" a string ".txt" to "numpy.ndarray" which looks like it is coming from the variable filename. Make sure your filename variable is the actual file name you want to write to and not numpy array.