收到无效的语法错误

Question

Apologies in advance for what I know will be a simple problem. I'm a total beginner to Python, but have decided to use it to write a mapreduce doing sentiment analysis.

I have taken a python file from this link: http://www.alex-hanna.com/tworkshops/lesson-6-basic-sentiment-analysis/ to give me guidance and am trying to run it. The code for the particular thing I have problems with is:

…
if len(sys.argv) < 2:
   print "Usage: avgNReduce.py "
   sys.exit(0)
…

The error is:

   if len(sys.argv) < 2:
                       ^
   SyntaxError: invalid syntax

I'm assuming this is a basic problem to resolve, but despite googling it I don't really know how I'm meant to fix this. I've tried using a colon instead of a semi colon and have ensured the ampersand was correct from the copying over. Any ideas?

Answer 1

You're looking for the < operator there instead of lt . ( lt stands for the less than operator in HTML, see this thread.)

if len(sys.argv) < 2:
    print "Usage: avgNReduce.py "
    sys.exit(0)