uproot.Cursor
Defined in uproot.source.cursor on line 31.
- class uproot.source.cursor.Cursor(index: int, origin: int = 0, refs: dict | None = None)
- Parameters:
- index (int) – Global seek position in the ROOT file or local position in an uncompressed uproot.source.chunk.Chunk. 
- origin (int) – Zero-point for numerical keys in - refs.
- refs (None or dict) – References to data already read in uproot.deserialization.read_object_any. 
 
 - Represents a seek point in a ROOT file, which may be held for later reference or advanced while interpreting data from a uproot.source.chunk.Chunk. - A cursor also holds references to previously read data that might be requested by uproot.deserialization.read_object_any. 
index
- Cursor.index
- Global seek position in the ROOT file or local position in an uncompressed uproot.source.chunk.Chunk. 
origin
refs
- Cursor.refs
- References to data already read in uproot.deserialization.read_object_any. 
displacement
- Cursor.displacement(other: Cursor = None) int
- The number of bytes between this uproot.Cursor and its origin (if None) or the - otheruproot.Cursor (if provided).- If the displacement is positive, - selfis later in the file than the- originor- other; if negative, it is earlier.
copy
- Cursor.copy(link_refs: bool = True) Cursor
- Returns a copy of this uproot.Cursor. If - link_refsis True, any refs will be referenced, rather than copied.
move_to
skip
skip_after
skip_over
- Cursor.skip_over(chunk: Chunk, context: dict)
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
 
 - Move the index to a seek position beyond the serialized data for an object that can be interpreted with uproot.deserialization.numbytes_version. - Returns True if successful (cursor has moved), False otherwise (cursor has NOT moved). 
fields
- Cursor.fields(chunk: Chunk, format: Struct, context: dict, move: bool = True)
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- format ( - struct.Struct) – Specification to interpret the bytes of data.
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index with a specified format. Returns a tuple of data whose types and length are determined by the - format.
field
- Cursor.field(chunk: Chunk, format: Struct, context: dict, move: bool = True)
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- format ( - struct.Struct) – Specification to interpret the bytes of data.
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index with a format that only specifies one field, returning a single item instead of a tuple. 
double32
- Cursor.double32(chunk: Chunk, context: dict, move: bool = True) float
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as ROOT’s - Double32_ttype, returning the Python- float.
float16
- Cursor.float16(chunk: Chunk, num_bits: int, context: dict, move: bool = True) float
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- num_bits (int) – Number of bits in the mantissa. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as ROOT’s - Float16_ttype, returning the Python- float.
byte
- Cursor.byte(chunk: Chunk, context: dict, move: bool = True)
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a raw byte. 
bytes
- Cursor.bytes(chunk, length, context, move=True)
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- length (int) – Number of bytes to retrieve. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as raw bytes with a given - length.
array
- Cursor.array(chunk: Chunk, length: int, dtype: dtype, context: dict, move: bool = True) ndarray
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- length (int) – Number of bytes to retrieve. 
- dtype ( - numpy.dtype) – Data type for the array.
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a one-dimensional array with a given - lengthand- dtype.
bytestring
- Cursor.bytestring(chunk: Chunk, context: dict, move: bool = True) bytes
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a bytestring. - The first byte is taken to be the length of the subsequent string unless it is equal to 255, in which case, the next 4 bytes are taken to be an - numpy.int32length.
string
- Cursor.string(chunk: Chunk, context: dict, move: bool = True) str
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a UTF-8 encoded string. - The first byte is taken to be the length of the subsequent string unless it is equal to 255, in which case, the next 4 bytes are taken to be an - numpy.int32length.
bytestring_with_length
- Cursor.bytestring_with_length(chunk: Chunk, context: dict, length: int, move: bool = True) bytes
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- length (int) – Number of bytes in the bytestring. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a bytestring. 
string_with_length
- Cursor.string_with_length(chunk: Chunk, context: dict, length: int, move: bool = True) str
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- length (int) – Number of bytes in the string. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a UTF-8 encoded string. 
classname
- Cursor.classname(chunk: Chunk, context: dict, move: bool = True) str
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Buffer of contiguous data from the file uproot.source.chunk.Source. 
- context (dict) – Auxiliary data used in deserialization. 
- move (bool) – If True, move the index past the fields; otherwise, leave it where it is. 
 
 - Interpret data at this index as a null-terminated, UTF-8 encoded string. 
rntuple_string
rntuple_datetime
debug
- Cursor.debug(chunk: ~uproot.source.chunk.Chunk, context: dict = {}, limit_bytes: int | None = None, dtype: ~numpy.dtype = None, offset: int = 0, stream=<_io.TextIOWrapper name='<stdout>' mode='w' encoding='utf-8'>)
- Parameters:
- chunk (uproot.source.chunk.Chunk) – Data to examine. 
- context (dict) – Auxiliary data used in deserialization. 
- limit_bytes (None or int) – Number of bytes to limit the output to. A line of debugging output (without any - offset) is 20 bytes, so multiples of 20 show full lines. If None, everything is shown to the end of the uproot.source.chunk.Chunk, which might be large.
- dtype (None, - numpy.dtype, or its constructor argument) – If None, present only the bytes as decimal values (0-255). Otherwise, also interpret them as an array of a given NumPy type.
- offset (int) – Number of bytes to skip before interpreting a - dtype; can be helpful if the numerical values are out of phase with the first byte shown. Not to be confused with- skip_bytes, which determines which bytes are shown at all. Any- offsetvalues that are equivalent modulo- dtype.itemsizeshow equivalent interpretations.
- stream (object with a - write(str)method) – Stream to write the debugging output to.
 
 - Peek at data by printing it to the - stream(usually stdout). The data are always presented as decimal bytes and ASCII characters, but may also be interpreted as numbers.- Example output with - dtype=">f4"and- offset=3.- --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+- 123 123 123 63 140 204 205 64 12 204 205 64 83 51 51 64 140 204 205 64 { { { ? --- --- --- @ --- --- --- @ S 3 3 @ --- --- --- @ 1.1 2.2 3.3 4.4 --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+- 176 0 0 64 211 51 51 64 246 102 102 65 12 204 205 65 30 102 102 66 --- --- --- @ --- 3 3 @ --- f f A --- --- --- A --- f f B 5.5 6.6 7.7 8.8 9.9 --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+- 202 0 0 67 74 0 0 67 151 128 0 123 123 --- --- --- C J --- --- C --- --- --- { { 101.0 202.0 303.0