Q:

How to read in multiple files and store as multiple arrays?

I am trying to read in files with python, extract a list of values and convert those values to an array so I will get 1 separate array for each file read.
I have tried the .append function however this seems to only add the subsequent lists to the first array created e.g. array 0 = list 0, array 1 = list 0 + list 1
d={}
tup=0
energy =[]
for i in range(len(file_path)):     #iterate for i = n number of files
    filename = os.path.basename(file_path[tup])
    s=open(filename, 'r')
    paths =os.path.basename(''.join(file_path[tup])) #sets path name as filename
    s=open(filename, 'r')
    f1 = s.readlines()           #reads lines in open file  
    s.close()                    #closes file    
    for z, line in enumerate(f1):             
        if "cell  1" in line:      #searches for phrase 'cell 1' in file 
            for x in f1[z+2:z+1004]:     #copies values in target range
                energy.append((float((x.split(None, 1)[0]))))     #appends only first values from target range to energy list            
    d['arrayx{0}'.format(tup)]= numpy.array(energy)

    tup +=1
print('array 0 ', d['arrayx0'])
print('array 1 ', d['arrayx1']) 
print('array 2 ', d['arrayx2'])  

let's say the extracted values for 3 files are the following:
A = [1,2,3]
B = [4,5,6]
C = [7,8,9]

I would expect the output from each print statement to be the following:
array 0 [1,2,3]
array 1 [4,5,6]
array 2 [7,8,9]

instead what I actually get is:
array 0 [1,2,3]
array 1 [1,2,3,4,5,6]
array 2 [1,2,3,4,5,6,7,8,9]

A:

You should move the initialization of energy into the main loop:
for i in range(len(file_path)):     #iterate for i = n number of files
   energy =[]
   ...

Otherwise energy keeps its value from one iteration to the next, giving the result you observe.

