I calculated a cosine similarity matrix with cosine\_similarity from sklearn.metrics.pairwise.

```
Matrix:
       2414514  413915  419480  473104  534621  609406    654913    654914  \
2414514  1.000000     0.0     0.0     0.0     0.0     0.0  0.755929  0.755929
413915   0.000000     1.0     0.0     0.0     0.0     1.0  0.000000  0.000000
419480   0.000000     0.0     1.0     1.0     1.0     0.0  0.000000  0.000000
473104   0.000000     0.0     1.0     1.0     1.0     0.0  0.000000  0.000000
534621   0.000000     0.0     1.0     1.0     1.0     0.0  0.000000  0.000000
609406   0.000000     1.0     0.0     0.0     0.0     1.0  0.000000  0.000000
654913   0.755929     0.0     0.0     0.0     0.0     0.0  1.000000  1.000000
654914   0.755929     0.0     0.0     0.0     0.0     0.0  1.000000  1.000000
668130   0.000000     0.0     0.0     0.0     0.0     0.0  0.000000  0.000000
668743   0.000000     0.0     0.0     0.0     0.0     0.0  0.000000  0.000000
679691   0.000000     0.0     0.0     0.0     0.0     0.0  0.000000  0.000000
707669   0.000000     0.0     0.0     0.0     0.0     0.0  0.000000  0.000000
749049   0.000000     1.0     0.0     0.0     0.0     1.0  0.000000  0.000000
770946   0.000000     0.0     0.0     0.0     0.0     0.0  0.000000  0.000000

         668130  668743  679691  707669  749049  770946
2414514     0.0     0.0     0.0     0.0     0.0     0.0
413915      0.0     0.0     0.0     0.0     1.0     0.0
419480      0.0     0.0     0.0     0.0     0.0     0.0
473104      0.0     0.0     0.0     0.0     0.0     0.0
534621      0.0     0.0     0.0     0.0     0.0     0.0
609406      0.0     0.0     0.0     0.0     1.0     0.0
654913      0.0     0.0     0.0     0.0     0.0     0.0
654914      0.0     0.0     0.0     0.0     0.0     0.0
668130      1.0     1.0     0.0     1.0     0.0     0.0
668743      1.0     1.0     0.0     1.0     0.0     0.0
679691      0.0     0.0     1.0     0.0     0.0     1.0
707669      1.0     1.0     0.0     1.0     0.0     0.0
749049      0.0     0.0     0.0     0.0     1.0     0.0
770946      0.0     0.0     1.0     0.0     0.0     1.0

```

But every day, i've new items. Is there a way to update the existing matrix with the new items without calculate all items?