On Fri, Feb 20, 2015 at 4:51 PM, Mark Lawrence <breamore...@yahoo.co.uk> wrote:
> On 20/02/2015 17:56, Chris Stinemetz wrote: > > Please don't top post as it makes long threads difficult if not impossible > to follow, thanks. > > I am getting closer. I think I have figured out the logic. I just have a >> quick question. How do you access key:values in a nested dictionary? >> >> MOL02997_C': [{'2': '0', '7': '0', '8': '0', '9': '0'}]} >> > > >> say I want to access the key:value 8:0 >> >> print dict['MOL02997_C']['8'] doesn't seem to work. >> > > "doesn't seem to work" doesn't tell us much, so normally you would post > your code and the full traceback that you get. However what you have seems > to be a dictionary that you've called dict, hence overriding the Python > built-in name. This isn't illegal but it's certainly frowned upon. For > the key 'MOL02997_C' you have a list which holds one dict which contains a > value '8' amongst others. Hence:- > > >>> mystruct = {'MOL02997_C': [{'2': '0', '7': '0', '8': '0', '9': '0'}]} > >>> mystruct > {'MOL02997_C': [{'7': '0', '8': '0', '2': '0', '9': '0'}]} > >>> mystruct['MOL02997_C'] > [{'7': '0', '8': '0', '2': '0', '9': '0'}] > >>> mystruct['MOL02997_C'][0] > {'7': '0', '8': '0', '2': '0', '9': '0'} > >>> mystruct['MOL02997_C'][0]['8'] > '0' > > Got that? > > > Thank you Mark. I understand what you are explaining to me but I am not sure why every instance of the key 8:value changes when I assign a new value to it. I am expecting only vals['KSL04523_A'][0]['8'] value to change to 55.55 but as you can see bellow all rows in the dictionary are changes for key 8: Thank you in advance >>> vals['KSL04523_A'] [{'7': '0', '9': '0', '8': '0', '2': '0'}] >>> vals['KSL04523_A'][0] {'7': '0', '9': '0', '8': '0', '2': '0'} >>> vals['KSL04523_A'][0]['8'] '0' >>> vals['KSL04523_A'][0]['8'] = 55.55 >>> pprint.pprint(vals) {'CELL_': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04514_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04514_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04515_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04515_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04515_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04516_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04516_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04516_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04517_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04517_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04517_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04519_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04519_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04519_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04520_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04520_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04520_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04521_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04521_B': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04521_C': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}], 'KSL04523_A': [{'2': '0', '7': '0', '8': 55.55, '9': '0'}]} _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor