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POSelect from list by index, but keep other associated items in list
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copied!<p>If I have a 2dlist of points like this... </p> <pre><code>myList=[['ab','0_3','-1','1'],['bm','2_1','-3','2'],['am','4_1','-1','3'],...]] </code></pre> <p>where <code>'-1','1'</code> for example are x, y coordinates (the last 2 columns) and I want display just part of the list with its index like this...</p> <pre><code>[0] ab # I don't want to display the other list items, just the index and first col [1] bm [2] am </code></pre> <p>...so the user can select one of them by index number to make a point of origin. I figured I could enumerate as such...</p> <pre><code>for row in enumerate(myList): i, a= row col= (i, a[0]) newList.append(col) print cols </code></pre> <p>But once I ask the user to select one ie. user selects '0' and that sets the variable <code>origin='ab'</code>, how can I get the x,y (or [2],[3]) columns associated with origin to use as the origin coordinates (I need to be able to compare to the rest of the list)?</p> <p>Using this method, can I somehow use the variable assigned to the selected point ie. <code>origin = ab</code>, and then get it's x,y and assign them to x1, y1... Because enumerate gives the 2 tuples (i, a) and appends them to <code>newList</code>, is that all I have in <code>newList</code>, or can I also append the other columns but not display them? I hope my explanation is clear enough... I only have badly butchered code atm</p> <hr> <p>So I finally got most of this working with...</p> <pre><code>import csv myList=[] try: csvr = open('testfile.csv','r') next(csvr, None) theList = csv.reader(csvr) for row in theList: myList.append(row) for row in enumerate(myList): i, a = row print i, a[0] except IOError: print 'Error!!!' try: choice = raw_input("Select a set: ") # Can also enter 'e' if choice=='e' print 'exiting' else: pass user_choice = myList[int(choice)] name, id, x, y= user_choice print name, id, return float(x), float(y) except: print 'error' </code></pre> <p>It prints as expected and I can return x, y now which is great but it just keeps prompting me to enter a number. Any suggestions?</p>

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