# ds1000 / 731

- taskset: [ds1000](https://harnessreport.com/tasks/ds1000.md)
- difficulty: 
- category: 
- language: 
- runnable from the site: no
- agent timeout: 1800s

## Results by harness

_none yet_

## Instruction

```
# 731: DS-1000 Task

## Prompt
Problem:
I have two csr_matrix, c1, c2.

I want a new matrix Feature = [c1, c2]. But if I directly concatenate them horizontally this way, there's an error that says the matrix Feature is a list. How can I achieve the matrix concatenation and still get the same type of matrix, i.e. a csr_matrix?

And it doesn't work if I do this after the concatenation: Feature = csr_matrix(Feature) It gives the error:

Traceback (most recent call last):
  File "yelpfilter.py", line 91, in <module>
    Feature = csr_matrix(Feature)
  File "c:\python27\lib\site-packages\scipy\sparse\compressed.py", line 66, in __init__
    self._set_self( self.__class__(coo_matrix(arg1, dtype=dtype)) )
  File "c:\python27\lib\site-packages\scipy\sparse\coo.py", line 185, in __init__
    self.row, self.col = M.nonzero()
TypeError: __nonzero__ should return bool or int, returned numpy.bool_

A:
<code>
from scipy import sparse
c1 = sparse.csr_matrix([[0, 0, 1, 0], [2, 0, 0, 0], [0, 0, 0, 0]])
c2 = sparse.csr_matrix([[0, 3, 4, 0], [0, 0, 0, 5], [6, 7, 0, 8]])
</code>
Feature = ... # put solution in this variable
BEGIN SOLUTION
<code>

## What to do
- Edit `solution/solution.py` so the code passes the DS-1000 tests.
- Do not access the internet or install new packages; required libraries are preinstalled in the Docker image.
- Run tests locally via `bash tests/test.sh`.

## Notes
- Keep the variable names/signatures implied by the prompt/code_context.
- The evaluator uses the original DS-1000 `code_context` (`test_execution` / `test_string`).
```
---
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