[Tutor] KeyError?

[Prasad, Ramit]

From: tutor-bounces+ramit.prasad=jpmchase.com at python.org [mailto:tutor-bounces+ramit.prasad=jpmchase.com at python.org] On Behalf Of Shwinn Ricci
Sent: Thursday, July 28, 2011 10:51 AM
To: tutor at python.org
Subject: [Tutor] KeyError?

I have an excel file that I am reading cell values from and putting them into a dictionary. the dictionary looks like this:

scafPositions = {position[j]: direction[j]}

where position[j] is exclusively floating/numerical values and direction[j] is exclusively strings.

When I try to find whether a test value val is in the array of positions, and then try to look its direction up with ScafPositions[val], I get a KeyError. Is this because my data isn't standalone numbers, but numbers that are calculated based off other cells? Or can I not test for val?
======================================

Your problem is probably that you are reassigning a new dictionary to the name scafPositions each time instead of updating it. You should have something like the following.

scafPositions = {}

#loop structure here:
    #do stuff
    scafPositions[ position[j] ] = direction[j]



Ramit


Ramit Prasad | JPMorgan Chase Investment Bank | Currencies Technology
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