How to fix ' 'str' object has no attribute 'tell' ' error in Python when trying to read xpt files?

Question

I am five .xpt data files which I am trying to read in python. I want to ge the data in those files into an array. This is for a machine learning project. I am trying that with this code but am getting an error on the line 'with xport.Reader(fname) as reader: '. Though I am still not sure if fixing this error would fix the whole code or now. Is there any other method I can use?

# imports to read the xpt file data 
import xport
import numpy as np
import os

#read the xpt file data
FN = ["BMX.XPT", "BMX_B.XPT", "BMX_C.XPT", "BMX_D.XPT", "BMX_E.XPT"]

def get_data(fname):
    Z={}
    H=None

    with xport.Reader(fname) as reader:
        for row in reader:

            if H is None:
                H=row.keys()
                H.remove("SEQN")
                H.sort()
            Z[row["SEQN"]] = [row[k] for k in H]

    return Z,H

# call get_data method on each file
D,VN =[],[]
for fn in FN:
    fn_full = os.path.join("../Data/", fn)
    X,H = get_data(fn_full)
    s = fn.replace(".XPT", "")
    H = [s + ":" + x for x in H]
    D.append(X)
    VN += H

## The sequence numbers that are in all data sets
KY = set(D[0].keys())
for d in D[1:]:
    KY &= set(d.keys())
KY = list(KY)
KY.sort()

def to_float(x):
    try:
        return float(x)
    except ValueError:
        return float("nan")

## Merge the data
Z = []
for ky in KY:

    z = []

    map(z.extend, (d[ky] for d in D))
    ## equivalent to
    ## for d in D:
    ##     z.extend(d[ky])

    z = [to_float(a) for a in z]
    ## equivalent to
    ## map(to_float, z)

    Z.append(z)

Z = np.array(Z)

Answer 1

It seems the input to xport.reader should be a file instead of a string. You should open it as a file instead of passing the file name as a parameter.

Eg

with xport.Reader(open(fname, ‘r’)) as reader:
    ....