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POPython dictionary with variables as keys
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copied!<p>I'm a Python newbie trying to parse a file to make a table of memory allocations. My input file is in the following format:</p> <pre><code>48 bytes allocated at 0x8bb970a0 24 bytes allocated at 0x8bb950c0 48 bytes allocated at 0x958bd0e0 48 bytes allocated at 0x8bb9b060 96 bytes allocated at 0x8bb9afe0 24 bytes allocated at 0x8bb9af60 </code></pre> <p>My first objective is to make a table that counts the instances of a particular number of byte allocations. In other words, my desired output for the above input would be something like:</p> <pre><code>48 bytes -> 3 times 96 bytes -> 1 times 24 bytes -> 2 times </code></pre> <p>(for now, I'm not concerned about the memory addresses)</p> <p>Since I'm using Python, I thought doing this using a dictionary would be the right way to go (based on about 3 hours' worth of reading Python tutorials). Is that a good idea?</p> <p>In trying to do this using a dictionary, I decided to make the number of bytes the 'key', and a counter as the 'value'. My plan was to increment the counter on every occurrence of the key. As of now, my code snippet is as follows:</p> <pre><code># Create an empty dictionary allocationList = {} # Open file for reading with open("allocFile.txt") as fp: for line in fp: # Split the line into a list (using space as delimiter) lineList = line.split(" ") # Extract the number of bytes numBytes = lineList[0]; # Store in a dictionary if allocationList.has_key('numBytes') currentCount = allocationList['numBytes'] currentCount += 1 allocationList['numBytes'] = currentCount else allocationList['numBytes'] = 1 for bytes, count in allocationList.iteritems() print bytes, "bytes -> ", count, " times" </code></pre> <p>With this, I get a syntax error in the 'has_key' call, which leads me to question whether it is even possible to use variables as dictionary keys. All examples I have seen so far assume that keys are available upfront. In my case, I can get my keys only when I'm parsing the input file.</p> <p>(Note that my input file can run into thousands of lines, with hundreds of different keys)</p> <p>Thank you for any help you can provide.</p>

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