Pandas pivot to sparse

from scipy.sparse import csr_matrix
from pandas.api.types import CategoricalDtype

person_c = CategoricalDtype(sorted(frame.person.unique()), ordered=True)
thing_c = CategoricalDtype(sorted(frame.thing.unique()), ordered=True)

row = frame.person.astype(person_c).cat.codes
col = frame.thing.astype(thing_c).cat.codes
sparse_matrix = csr_matrix((frame["count"], (row, col)), \
                           shape=(person_c.categories.size, thing_c.categories.size))

>>> sparse_matrix
<3x4 sparse matrix of type '<class 'numpy.int64'>'
     with 6 stored elements in Compressed Sparse Row format>

>>> sparse_matrix.todense()
matrix([[0, 1, 0, 1],
        [1, 0, 0, 1],
        [1, 0, 1, 0]], dtype=int64)


dfs = pd.SparseDataFrame(sparse_matrix, \
                         index=person_c.categories, \
                         columns=thing_c.categories, \
                         default_fill_value=0)
>>> dfs
        a   b   c   d
 him    0   1   0   1
  me    1   0   0   1
 you    1   0   1   0

Source: stackoverflow.com

Similar codes

-1 vote156 views1 answer
Python plt show legend
Python
0 vote179 views1 answer
Calculate vif in python
Python
21 votes172 views6 answers
Python simple server
Python
0 vote165 views1 answer
Change command aliad
Python
1 vote168 views2 answers
'str' object has no attribute 'strftime'
Python
0 vote193 views1 answer
Import pil pycharm
Python
21 votes177 views2 answers
How to update python
Python
0 vote178 views1 answer
Index and reversing a sub list in python list
Python
0 vote192 views2 answers
Fetching data from multiple tables using related name in django
Python Django
2 votes148 views1 answer
Use of == python
Python