python - Fastest way from logic matrix to list of sets -

-

i need convert sparse logic matrix list of sets, each list[i] contains set of rows nonzero values column[i]. following code works, i'm wondering if there's faster way this. actual data i'm using approx 6000x6000 , more sparse example.

import numpy np  = np.array([[1, 0, 0, 0, 0, 1],               [0, 1, 1, 1, 1, 0],               [1, 0, 1, 0, 1, 1],               [1, 1, 0, 1, 0, 1],               [1, 1, 0, 1, 0, 0],               [1, 0, 0, 0, 0, 0],               [0, 0, 1, 1, 1, 0],               [0, 0, 1, 0, 1, 0]])  rows,cols = a.shape  c = np.nonzero(a) d = [set() j in range(cols)]  in range(len(c[0])):     d[c[1][i]].add(c[0][i])  print d

if represent sparse array csc_matrix, can use indices , indptr attributes create sets.

for example,

in [93]: out[93]:  array([[1, 0, 0, 0, 0, 1],        [0, 1, 1, 1, 1, 0],        [1, 0, 1, 0, 1, 1],        [1, 1, 0, 1, 0, 1],        [1, 1, 0, 1, 0, 0],        [1, 0, 0, 0, 0, 0],        [0, 0, 1, 1, 1, 0],        [0, 0, 1, 0, 1, 0]])  in [94]: scipy.sparse import csc_matrix  in [95]: c = csc_matrix(a)  in [96]: c.indptr out[96]: array([ 0,  5,  8, 12, 16, 20, 23], dtype=int32)  in [97]: c.indices out[97]: array([0, 2, 3, 4, 5, 1, 3, 4, 1, 2, 6, 7, 1, 3, 4, 6, 1, 2, 6, 7, 0, 2, 3], dtype=int32)  in [98]: d = [set(c.indices[c.indptr[i]:c.indptr[i+1]]) in range(c.shape[1])]  in [99]: d out[99]:  [{0, 2, 3, 4, 5},  {1, 3, 4},  {1, 2, 6, 7},  {1, 3, 4, 6},  {1, 2, 6, 7},  {0, 2, 3}]

for list of arrays instead of sets, don't call set():

in [100]: [c.indices[c.indptr[i]:c.indptr[i+1]] in range(len(c.indptr)-1)] out[100]:  [array([0, 2, 3, 4, 5], dtype=int32),  array([1, 3, 4], dtype=int32),  array([1, 2, 6, 7], dtype=int32),  array([1, 3, 4, 6], dtype=int32),  array([1, 2, 6, 7], dtype=int32),  array([0, 2, 3], dtype=int32)]

Comments

Post a Comment

Popular posts from this blog

wordpress - (T_ENDFOREACH) php error -

-
creating wordpress website , i'm getting following php error: parse error: syntax error, unexpected 'endforeach' (t_endforeach) in /home/soralmedia/public_html/wp-content/themes/soral media/woocommerce/myaccount/my-orders.php on line 98 here's code file: <?php /** * orders * * shows recent orders on account page. * * template can overridden copying yourtheme/woocommerce/myaccount/my-orders.php. * * however, on occasion woocommerce need update template files , (the theme developer). * need copy new files theme maintain compatibility. try this. * little possible, happen. when occurs version of template file will. * bumped , readme list important changes. * * @see http://docs.woothemes.com/document/template-structure/ * @author woothemes * @package woocommerce/templates * @version 2.5.0 */ if ( ! defined( 'abspath' ) ) { exit; } $my_orders_columns = apply_filters( 'woocommerce_my_account_my_orders_columns', array( ...
Read more

Export Excel workseet into txt file using vba - (text and numbers with formulas) -

-
i new vba have developed code use in excel move text/numbers txt file. issue have 3 functions need go same txt file. when run first function has set fs = createobject("scripting.filesystemobject") set = fs.createtextfile(module1.nys45uploadfilename, true) a.writeline (str) a.close. the other 2 functions had save. set fs = createobject("scripting.filesystemobject") set = fs.savetextfile(module1.nys45uploadfilename, true) a.writeline (str) a.close. the first function go txt file, other 2 error object doesn't support property or method. when changed 3 create last function goes txt file. can not figure out word use in order make other 2 functions follow txt file in order keyed. the entire code follows private sub addrecord_click() on error goto errhandler module1.nys45uploadfilename = application.getsaveasfilename(filefilter:="textfiles (*.txt), *.txt") if module1.nys45uploadfilename = "false" exit sub ...
Read more

Using django-mptt to get only the categories that have items -

-
sample structure: all uppercase: category mixed case: item root ├── books │   ├── fiction │   │   └── classics │   └── non-fiction ├── clothing └── electronics ├── laptops ├── phones │   ├── apple │   │   ├── iphone 6 │   │   ├── iphone 6 plus │   │   ├── iphone 6s │   │   └── iphone 6s plus │   ├── motorola │   │   ├── moto g4 │   │   ├── moto g4 play │   │   ├── moto g4 plus │   │   └── moto x │   └── samsung └── tablets └── apple i'm trying have index page show "electronics" category. "clothing" category shouldn't show since it's empty , "books" category shouldn't show either since, although has child categories, child categories don't have items. similarly, "electronics" page should show "phones" category. "laptops" category shouldn't show since it's empty , "tablets" category shouldn't show either since...
Read more