Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>As ~unutbu said, try the <a href="http://wiki.python.org/moin/PythonDecoratorLibrary#Memoize" rel="nofollow noreferrer">memoized decorator</a> and the following changes:</p> <pre><code>@memoized def search(a, b): # Initialize startup variables. nodes, index = [], [] a_size, b_size = len(a), len(b) # Begin to slice the sequences. for size in range(min(a_size, b_size), 0, -1): for a_addr in range(a_size - size + 1): # Slice "a" at address and end. a_term = a_addr + size a_root = list(a)[a_addr:a_term] #change to list for b_addr in range(b_size - size + 1): # Slice "b" at address and end. b_term = b_addr + size b_root = list(b)[b_addr:b_term] #change to list # Find out if slices are equal. if a_root == b_root: # Create prefix tree to search. a_pref, b_pref = list(a)[:a_addr], list(b)[:b_addr] p_tree = search(a_pref, b_pref) # Create suffix tree to search. a_suff, b_suff = list(a)[a_term:], list(b)[b_term:] s_tree = search(a_suff, b_suff) # Make completed slice objects. a_slic = Slice(a_pref, a_root, a_suff) b_slic = Slice(b_pref, b_root, b_suff) # Finish the match calculation. value = size + p_tree.value + s_tree.value match = Match(a_slic, b_slic, p_tree, s_tree, value) # Append results to tree lists. nodes.append(match) index.append(value) # Return largest matches found. if nodes: return Tree(nodes, index, max(index)) # Give caller null tree object. return Tree(nodes, index, 0) </code></pre> <p>For memoization, dictionaries are best, but they cannot be sliced, so they have to be changed to lists as indicated in the comments above.</p>
    singulars
    1. This table or related slice is empty.
    1. POHow can memoization be applied to this algorithm?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USkzh
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POHow can memoization be applied to this algorithm?
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    1. COThanks for your help! As noted above, the code was written for sequences [that support slicing] (list, tuple, string, bytes, bytearray, and any custom-made containers). From your change, it appears that immutable sequences are needed for correct memoization.
      singulars
      1. PO
      1. USNoctis Skytower
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload