I am try to save a matrix in R and reload in python

# R
Matrix::writeMM(data_matrix, file='/path/to/data_matrix.mtx')

# also reload to test
#data_matrix <- Matrix::readMM(file='/path/to/data_matrix.mtx')

# shell
head /path/to/data_matrix.mtx
%%MatrixMarket matrix coordinate integer general
26621 11089 32120337
1 1 1
9 1 1
14 1 1
15 1 2
18 1 3
21 1 1
34 1 2
35 1 3

# reload in python
import io
data_input = io.mmread('/path/to/data_matrix.mtx')

I got following error:

/path/to/python3.9/site-packages/scipy/io/_fast_matrix_market/__init__.py:197, in _get_read_cursor(source, parallelism)
    195         ret_stream_to_close = source
...
--> 197         return _fmm_core.open_read_file(path, parallelism), ret_stream_to_close
    199 # Stream object.
    200 if hasattr(source, "read"):
ValueError: Line 1: Not a Matrix Market file. Missing banner.

I don’t know where the problem occurred.