Coverage for /var/srv/projects/api.amasfac.comuna18.com/tmp/venv/lib/python3.9/site-packages/pandas/core/interchange/buffer.py: 47%

1from __future__ import annotations 

2 

3import numpy as np 

4 

5from pandas.core.interchange.dataframe_protocol import ( 

6 Buffer, 

7 DlpackDeviceType, 

8) 

9from pandas.util.version import Version 

10 

11_NUMPY_HAS_DLPACK = Version(np.__version__) >= Version("1.22.0") 

12 

13 

14class PandasBuffer(Buffer): 

15 """ 

16 Data in the buffer is guaranteed to be contiguous in memory. 

17 """ 

18 

19 def __init__(self, x: np.ndarray, allow_copy: bool = True) -> None: 

20 """ 

21 Handle only regular columns (= numpy arrays) for now. 

22 """ 

23 if not x.strides == (x.dtype.itemsize,): 

24 # The protocol does not support strided buffers, so a copy is 

25 # necessary. If that's not allowed, we need to raise an exception. 

26 if allow_copy: 

27 x = x.copy() 

28 else: 

29 raise RuntimeError( 

30 "Exports cannot be zero-copy in the case " 

31 "of a non-contiguous buffer" 

32 ) 

33 

34 # Store the numpy array in which the data resides as a private 

35 # attribute, so we can use it to retrieve the public attributes 

36 self._x = x 

37 

38 @property 

39 def bufsize(self) -> int: 

40 """ 

41 Buffer size in bytes. 

42 """ 

43 return self._x.size * self._x.dtype.itemsize 

44 

45 @property 

46 def ptr(self) -> int: 

47 """ 

48 Pointer to start of the buffer as an integer. 

49 """ 

50 return self._x.__array_interface__["data"][0] 

51 

52 def __dlpack__(self): 

53 """ 

54 Represent this structure as DLPack interface. 

55 """ 

56 if _NUMPY_HAS_DLPACK: 

57 return self._x.__dlpack__() 

58 raise NotImplementedError("__dlpack__") 

59 

60 def __dlpack_device__(self) -> tuple[DlpackDeviceType, int | None]: 

61 """ 

62 Device type and device ID for where the data in the buffer resides. 

63 """ 

64 return (DlpackDeviceType.CPU, None) 

65 

66 def __repr__(self) -> str: 

67 return ( 

68 "PandasBuffer(" 

69 + str( 

70 { 

71 "bufsize": self.bufsize, 

72 "ptr": self.ptr, 

73 "device": self.__dlpack_device__()[0].name, 

74 } 

75 ) 

76 + ")" 

77 )