擅长:python、mysql、java
<pre><code>file_name=input("Enter the Filename: ")
# use "with" block to open file
# to ensure the file is closed once your code is done with it
with open(file_name,'r') as infile:
# create "nlist" here and append each element to it during iteration
nlist=[]
for line in infile:
line_str=line.split()
# no need to iterate with range(len()); use a list comprehension
# to map "float" to each list element
line_str = [float(element) for element in line_str]
nlist.append(line_str)
print(nlist)
</code></pre>