quantify_core.data

types

Module containing the core data concepts of quantify.

class TUID(value: str)

A human readable unique identifier based on the timestamp. This class does not wrap the passed in object but simply verifies and returns it.

A tuid is a string formatted as YYYYmmDD-HHMMSS-sss-******. The tuid serves as a unique identifier for experiments in quantify.

See also

The. handling module.

classmethod datetime(tuid)

Return type:

datetime

Returns:

datetime object corresponding to the TUID

classmethod datetime_seconds(tuid)

Return type:

datetime

Returns:

datetime object corresponding to the TUID with microseconds discarded

classmethod is_valid(tuid)

Test if tuid is valid. A valid tuid is a string formatted as YYYYmmDD-HHMMSS-sss-******.

Parameters:

tuid (str) – a tuid string

Return type:

bool

Returns:

bool True if the string is a valid TUID.

Raises:

ValueError – Invalid format

classmethod uuid(tuid)

Return type:

str

Returns:

str the uuid (universally unique identifier) component of the TUID, corresponding to the last 6 characters.

handling

Utilities for handling data.

class DecodeToNumpy(list_to_ndarray=False, *args, **kwargs)

Decodes a JSON object to Python/Numpy objects.

__init__(list_to_ndarray=False, *args, **kwargs)

Decodes a JSON object to Python/Numpy objects.

Example

json.loads(json_string, cls=DecodeToNumpy, list_to_numpy=True)

Parameters:

• list_to_ndarray (bool (default: False)) – If True, will try to convert python lists to a numpy array.

• args – Additional args to be passed to json.JSONDecoder.

• kwargs – Additional kwargs to be passed to json.JSONDecoder.

_object_hook(obj)

Custom deserialization hook that converts lists to np.arrays.

Return type:

dict

_generate_long_name(settable)

Generate the long_name entry for a dataset coordinate for a settable.

The long name is based on the label of root instrument and all relevant submodules leading to the settable, including the settable. If no label is specified, the name attribute is used.

Return type:

str

_generate_name(settable)

Generate the name entry for a dataset coordinate for a settable.

The long name is based on the name of root instrument and all relevant submodules leading to the settable, including the settable.

Return type:

str

_instrument_submodules_settable(settable)

Returns a list containing the root instrument, submodules and settable (typically a Parameter).

For example, when passing current_source.module1.output3, this function will return [current_source, module1, output3].

Parameters:

settable (Settable) – The settable for which to get the instrument and ancestors.

Return type:

list[ParameterBase | InstrumentBase]

Returns:

: A list with the root instrument, all submodules and the settable.

_is_batched(obj)

N.B. This function cannot be imported from quantify_core.measurement.type due to some circular dependencies that it would create in the quantify_core.measurement.__init__.

Parameters:

obj (Settable or Gettable) – settable or gettable to be checked.

Return type:

bool

Returns:

: The .batched attribute of the settable/gettable obj, False if not present.

_is_uniformly_spaced_array(points, rel_tolerance=0.001)

Determines if the points in the array are spaced uniformly. Intended mainly for plotmon to detect if it needs to interpolate the data first, otherwise pyqtgraph cannot handle the non-uniform case.

Usually the points have been generated with numpy.linspace() or numpy.arange.

This function is intended to be detect cases such as adaptively sampled datasets, logspace, etc..

Parameters:

• points (ndarray) – A 1-dimensional array of points (usually the setpoints in an experiment).

• rel_tolerance (float (default: 0.001)) – Maximum relative tolerance with respect to the size of a segment that would be generated by a numpy.linspace(min(points), max(points), len(points) - 1). The function returns :code:`False if any segment in points violates this tolerance.

Return type:

bool

Returns:

: Whether the array is uniformly spaced and monotonously increasing or decreasing.

Examples

This function assumes unique values. This means that if there are duplicates in points this function will return False. E.g.,

>>> import quantify_core.data.handling as dh
... dh._is_uniformly_spaced_array([1, 2, 2, 3, 4])
False

Additionally, assumes monotonously increasing or decreasing values.

_vars_match(dsets, var_type='x')

Checks if all the datasets have matching xi or yi.

Return type:

bool

_xarray_numpy_bool_patch(dataset)

Converts any attribute of bool_ type to a bool.

This is a patch to a bug in xarray 0.17.0.

See also

See issue #161 in quantify-core. Our (accepted) pull request pydata/xarray#4986 Version >0.17.0 will fix the problem but will have breaking changes, for now we use this patch.

Parameters:

dataset (Dataset) – The dataset to be patched in-place.

Return type:

None

_xi_and_yi_match(dsets)

Checks if all xi and yi data variables in dsets match.

Returns True only when all these conditions are met: :rtype: bool

• Same number of xi’s

• Same number of yi’s

• Same attributes for xi’s across dsets

• Same attributes for yi’s across dsets

• Same order of the xi’s across dsets

• Same order of the yi’s across dsets

Otherwise returns False.

concat_dataset(tuids, dim='dim_0', name=None, analysis_name=None)

Takes in a list of TUIDs and concatenates the corresponding datasets. It adds the TUIDs as a coordinate in the new dataset.

By default, we will extract the unprocessed dataset from each directory, but if analysis_name is specified, we will extract the processed dataset for that analysis.

Parameters:

• tuids (list[TUID]) – List of TUIDs.

• dim (str (default: 'dim_0')) – Dimension along which to concatenate the datasets.

• analysis_name (Optional[str] (default: None)) – In the case that we want to extract the processed dataset for give analysis, this is the name of the analysis.

• name (Optional[str] (default: None)) – The name of the concatenated dataset. If None, use the name of the first dataset in the list.

Return type:

Dataset

Returns:

: Concatenated dataset with new TUID and references to the old TUIDs.

create_exp_folder(tuid, name=None, datadir=None)

Creates an empty folder to store an experiment container.

If the folder already exists, simply returns the experiment folder corresponding to the TUID.

Parameters:

• tuid (TUID) – A timestamp based human-readable unique identifier.

• name (str | None (default: None)) – Optional name to identify the folder.

• datadir (Path | str | None (default: None)) – path of the data directory. If None, uses get_datadir() to determine the data directory.

Return type:

str

Returns:

: Full path of the experiment folder following format: /datadir/YYYYmmDD/YYYYmmDD-HHMMSS-sss-******-name/.

default_datadir(verbose=True)

Returns (and optionally print) a default datadir path.

Intended for fast prototyping, tutorials, examples, etc..

Parameters:

verbose (bool (default: True)) – If True prints the returned datadir.

Return type:

Path

Returns:

: The Path.home() / "quantify-data" path.

extract_parameter_from_snapshot(snapshot, parameter)

A function which takes a parameter and extracts it from a snapshot, including in the case where the parameter is part of a nested submodule within a QCoDeS instrument.

Parameters:

• snapshot (dict[str, Any]) – The snapshot

• parameter (str) – The full address of the QCoDeS parameter as a string, in the format "instrument.submodule.submodule.parameter" (an arbitrary number of nested submodules is a allowed).

Return type:

dict[str, Any]

Returns:

: The dict specifying the parameter properties which was extracted from the snapshot

gen_tuid(time_stamp=None)

Generates a TUID based on current time.

Parameters:

time_stamp (datetime.datetime | None (default: None)) – Optional, can be passed to ensure the tuid is based on a specific time.

Return type:

TUID

Returns:

: Timestamp based uid.

get_datadir()

Returns the current data directory.

The data directory can be changed using set_datadir().

Return type:

str

Returns:

: The current data directory.

get_latest_tuid(contains='')

Returns the most recent tuid.

Tip

This function is similar to get_tuids_containing() but is preferred if one is only interested in the most recent TUID for performance reasons.

Parameters:

contains (str (default: '')) – An optional string contained in the experiment name.

Return type:

TUID

Returns:

: The latest TUID.

Raises:

FileNotFoundError – No data found.

get_tuids_containing(contains='', t_start=None, t_stop=None, max_results=9223372036854775807, reverse=False)

Returns a list of tuids containing a specific label.

Tip

If one is only interested in the most recent TUID, get_latest_tuid() is preferred for performance reasons.

Parameters:

• contains (str (default: '')) – A string contained in the experiment name.

• t_start (datetime.datetime | str | None (default: None)) – datetime to search from, inclusive. If a string is specified, it will be converted to a datetime object using parse. If no value is specified, will use the year 1 as a reference t_start.

• t_stop (datetime.datetime | str | None (default: None)) – datetime to search until, exclusive. If a string is specified, it will be converted to a datetime object using parse. If no value is specified, will use the current time as a reference t_stop.

• max_results (int (default: 9223372036854775807)) – Maximum number of results to return. Defaults to unlimited.

• reverse (bool (default: False)) – If False, sorts tuids chronologically, if True sorts by most recent.

Return type:

list[TUID]

Returns:

list A list of TUID: objects.

Raises:

FileNotFoundError – No data found.

get_varying_parameter_values(tuids, parameter)

A function that gets a parameter which varies over multiple experiments and puts it in a ndarray.

Parameters:

• tuids (list[TUID]) – The list of TUIDs from which to get the varying parameter.

• parameter (str) – The name and address of the QCoDeS parameter from which to get the value, including the instrument name and all submodules. For example "current_source.module0.dac0.current".

Return type:

ndarray

Returns:

: The values of the varying parameter.

grow_dataset(dataset)

Resizes the dataset by doubling the current length of all arrays.

Parameters:

dataset (Dataset) – The dataset to resize.

Return type:

Dataset

Returns:

: The resized dataset.

initialize_dataset(settable_pars, setpoints, gettable_pars)

Initialize an empty dataset based on settable_pars, setpoints and gettable_pars.

Parameters:

• settable_pars (Iterable) – A list of M settables.

• setpoints (list[ndarray]) – An (M*N) array.

• gettable_pars (Iterable) – A list of gettables.

Return type:

Dataset

Returns:

: The dataset.

load_dataset(tuid, datadir=None, name='dataset.hdf5')

Loads a dataset specified by a tuid.

Tip

This method also works when specifying only the first part of a TUID.

Note

This method uses load_dataset() to ensure the file is closed after loading as datasets are intended to be immutable after performing the initial experiment.

Parameters:

• tuid (TUID) – A TUID string. It is also possible to specify only the first part of a tuid.

• datadir (Path | str | None (default: None)) – Path of the data directory. If None, uses get_datadir() to determine the data directory.

• name (str (default: 'dataset.hdf5')) – Name of the dataset.

Return type:

xr.Dataset

Returns:

: The dataset.

Raises:

FileNotFoundError – No data found for specified date.

load_dataset_from_path(path)

Loads a Dataset with a specific engine preference.

Before returning the dataset AdapterH5NetCDF.recover() is applied.

This function tries to load the dataset until success with the following engine preference:

• "h5netcdf"

• "netcdf4"

• No engine specified (load_dataset() default)

Parameters:

path (Path | str) – Path to the dataset.

Return type:

xr.Dataset

Returns:

: The loaded dataset.

load_processed_dataset(tuid, analysis_name)

Given an experiment TUID and the name of an analysis previously run on it, retrieves the processed dataset resulting from that analysis.

Parameters:

• tuid (TUID) – TUID of the experiment from which to load the data.

• analysis_name (str) – Name of the Analysis from which to load the data.

Return type:

Dataset

Returns:

: A dataset containing the results of the analysis.

load_quantities_of_interest(tuid, analysis_name)

Given an experiment TUID and the name of an analysis previously run on it, retrieves the corresponding “quantities of interest” data.

Parameters:

• tuid (TUID) – TUID of the experiment.

• analysis_name (str) – Name of the Analysis from which to load the data.

Return type:

dict

Returns:

: A dictionary containing the loaded quantities of interest.

load_snapshot(tuid, datadir=None, list_to_ndarray=False, file='snapshot.json')

Loads a snapshot specified by a tuid.

Parameters:

• tuid (TUID) – A TUID string. It is also possible to specify only the first part of a tuid.

• datadir (Path | str | None (default: None)) – Path of the data directory. If None, uses get_datadir() to determine the data directory.

• list_to_ndarray (bool (default: False)) – Uses an internal DecodeToNumpy decoder which allows a user to automatically convert a list to numpy array during deserialization of the snapshot.

• file (str (default: 'snapshot.json')) – Filename to load.

Return type:

dict

Returns:

: The snapshot.

Raises:

FileNotFoundError – No data found for specified date.

locate_experiment_container(tuid, datadir=None)

Returns the path to the experiment container of the specified tuid.

Parameters:

• tuid (TUID) – A TUID string. It is also possible to specify only the first part of a tuid.

• datadir (Path | str | None (default: None)) – Path of the data directory. If None, uses get_datadir() to determine the data directory.

Return type:

str

Returns:

: The path to the experiment container

Raises:

FileNotFoundError – Experiment container not found.

multi_experiment_data_extractor(experiment, parameter, *, new_name=None, t_start=None, t_stop=None, analysis_name=None, dimension='dim_0')

A data extraction function which loops through multiple quantify data directories and extracts the selected varying parameter value and corresponding datasets, then compiles this data into a single dataset for further analysis.

By default, we will extract the unprocessed dataset from each directory, but if analysis_name is specified, we will extract the processed dataset for that analysis.

Parameters:

• experiment (str) – The experiment to be included in the new dataset. For example “Pulsed spectroscopy”

• parameter (str) – The name and address of the QCoDeS parameter from which to get the value, including the instrument name and all submodules. For example "current_source.module0.dac0.current".

• new_name (str | None (default: None)) – The name of the new multifile dataset. If no new name is given, it will create a new name as experiment vs instrument.

• t_start (str | None (default: None)) – Datetime to search from, inclusive. If a string is specified, it will be converted to a datetime object using parse. If no value is specified, will use the year 1 as a reference t_start.

• t_stop (str | None (default: None)) – Datetime to search until, exclusive. If a string is specified, it will be converted to a datetime object using parse. If no value is specified, will use the current time as a reference t_stop.

• analysis_name (str | None (default: None)) – In the case that we want to extract the processed dataset for give analysis, this is the name of the analysis.

• dimension (str | None (default: 'dim_0')) – The name of the dataset dimension to concatenate over

Return type:

xr.Dataset

Returns:

: The compiled quantify dataset.

set_datadir(datadir=None)

Sets the data directory.

Parameters:

datadir (Path | str | None (default: None)) – Path of the data directory. If set to None, resets the datadir to the default datadir (<top_level>/data).

Return type:

None

snapshot(update=False, clean=True)

State of all instruments setup as a JSON-compatible dictionary (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters:

• update (bool (default: False)) – If True, first gets all values before filling the snapshot.

• clean (bool (default: True)) – If True, removes certain keys from the snapshot to create a more readable and compact snapshot.

Return type:

dict

to_gridded_dataset(quantify_dataset, dimension='dim_0', coords_names=None)

Converts a flattened (a.k.a. “stacked”) dataset as the one generated by the initialize_dataset() to a dataset in which the measured values are mapped onto a grid in the xarray format.

This will be meaningful only if the data itself corresponds to a gridded measurement.

Note

Each individual (x0[i], x1[i], x2[i], ...) setpoint must be unique.

Conversions applied:

• The names "x0", "x1", ... will correspond to the names of the Dimensions.

• The unique values for each of the x0, x1, ... Variables are converted to

  Coordinates.

• The y0, y1, ... Variables are reshaped into a (multi-)dimensional grid

  and associated to the Coordinates.

See also

• Converting dataset coordinates from flat list to grid

• MeasurementControl.setpoints_grid()

Parameters:

• quantify_dataset (xr.Dataset) – Input dataset in the format generated by the initialize_dataset.

• dimension (str (default: 'dim_0')) – The flattened xarray Dimension.

• coords_names (Iterable | None (default: None)) – Optionally specify explicitly which Variables correspond to orthogonal coordinates, e.g. datasets holds values for ("x0", "x1") but only “x0” is independent: to_gridded_dataset(dset, coords_names=["x0"]).

Return type:

xr.Dataset

Returns:

: The new dataset.

trim_dataset(dataset)

Trim NaNs from a dataset, useful in the case of a dynamically resized dataset (e.g. adaptive loops).

Parameters:

dataset (Dataset) – The dataset to trim.

Return type:

Dataset

Returns:

: The dataset, trimmed and resized if necessary or unchanged.

write_dataset(path, dataset)

Writes a Dataset to a file with the h5netcdf engine.

Before writing the adapt() is applied.

To accommodate for complex-type numbers and arrays invalid_netcdf=True is used.

Parameters:

• path (Path | str) – Path to the file including filename and extension

• dataset (xr.Dataset) – The Dataset to be written to file.

Return type:

None

dataset_adapters

Utilities for dataset (python object) handling.

class AdapterH5NetCDF

Quantify dataset adapter for the h5netcdf engine.

It has the functionality of adapting the Quantify dataset to a format compatible with the h5netcdf xarray backend engine that is used to write and load the dataset to/from disk.

Warning

The h5netcdf engine has minor issues when performing a two-way trip of the dataset. The type of some attributes are not preserved. E.g., list- and tuple-like objects are loaded as numpy arrays of dtype=object.

classmethod adapt(dataset)

Serializes to JSON the dataset and variables attributes.

To prevent the JSON serialization for specific items, their names should be listed under the attribute named json_serialize_exclude (for each attrs dictionary).

Parameters:

dataset (Dataset) – Dataset that needs to be adapted.

Return type:

Dataset

Returns:

: Dataset in which the attributes have been replaced with their JSON strings version.

static attrs_convert(attrs, inplace=False, vals_converter=<function dumps>)

Converts to/from JSON string the values of the keys which are not listed in the json_serialize_exclude list.

Parameters:

• attrs (dict) – The input dictionary.

• inplace (bool (default: False)) – If True the values are replaced in place, otherwise a deepcopy of attrs is performed first.

Return type:

dict

classmethod recover(dataset)

Reverts the action of .adapt().

To prevent the JSON de-serialization for specific items, their names should be listed under the attribute named json_serialize_exclude (for each attrs dictionary).

Parameters:

dataset (Dataset) – Dataset from which to recover the original format.

Return type:

Dataset

Returns:

: Dataset in which the attributes have been replaced with their python objects version.

class DatasetAdapterBase

A generic interface for a dataset adapter.

Note

It might be difficult to grasp the generic purpose of this class. See AdapterH5NetCDF for a specialized use case.

A dataset adapter is intended to “adapt”/”convert” a dataset to a format compatible with some other piece of software such as a function, interface, read/write back end, etc.. The main use case is to define the interface of the AdapterH5NetCDF that converts the Quantify dataset for loading and writing to/from disk.

Subclasses implementing this interface are intended to be a two-way bridge to some other object/interface/backend to which we refer to as the “Target” of the adapter.

The function .adapt() should return a dataset to be consumed by the Target.

The function .recover() should receive a dataset generated by the Target.

abstract classmethod adapt(dataset)

Converts the dataset to a format consumed by the Target.

Return type:

Dataset

abstract classmethod recover(dataset)

Inverts the action of the .adapt() method.

Return type:

Dataset

class DatasetAdapterIdentity

A dataset adapter that does not modify the datasets in any way.

Intended to be used just as an object that respects the adapter interface defined by DatasetAdapterBase.

A particular use case is the backwards compatibility for loading and writing older versions of the Quantify dataset.

classmethod adapt(dataset)

Return type:

Dataset

Returns:

: Same dataset with no modifications.

classmethod recover(dataset)

Return type:

Dataset

Returns:

: Same dataset with no modifications.

dataset_attrs

Utilities for handling the attributes of xarray.Dataset and xarray.DataArray (python objects) handling.

class QCoordAttrs(unit='', long_name='', is_main_coord=None, uniformly_spaced=None, is_dataset_ref=False, json_serialize_exclude=<factory>)

A dataclass representing the required attrs attribute of main and secondary coordinates.

See also

Required dataset coordinate attributes

is_dataset_ref: bool = False

Flags if it is an array of quantify_core.data.types.TUID s of other dataset.

is_main_coord: bool | None = None

When set to True, flags the xarray coordinate to correspond to a main coordinate, otherwise (False) it corresponds to a secondary coordinate.

json_serialize_exclude: List[str]

A list of strings corresponding to the names of other attributes that should not be json-serialized when writing the dataset to disk. Empty by default.

long_name: str = ''

A long name for this coordinate.

uniformly_spaced: bool | None = None

Indicates if the values are uniformly spaced.

unit: str = ''

The units of the values.

class QDatasetAttrs(tuid=None, dataset_name='', dataset_state=None, timestamp_start=None, timestamp_end=None, quantify_dataset_version='2.0.0', software_versions=<factory>, relationships=<factory>, json_serialize_exclude=<factory>)

A dataclass representing the attrs attribute of the Quantify dataset.

See also

Required dataset attributes

dataset_name: str = ''

The dataset name, usually same as the the experiment name included in the name of the experiment container.

dataset_state: Literal[None, 'running', 'interrupted (safety)', 'interrupted (forced)', 'done'] = None

Denotes the last known state of the experiment/data acquisition that served to ‘build’ this dataset. Can be used later to filter ‘bad’ datasets.

json_serialize_exclude: List[str]

A list of strings corresponding to the names of other attributes that should not be json-serialized when writing the dataset to disk. Empty by default.

quantify_dataset_version: str = '2.0.0'

A string identifying the version of this Quantify dataset for backwards compatibility.

relationships: List[QDatasetIntraRelationship]

A list of relationships within the dataset specified as list of dictionaries that comply with the QDatasetIntraRelationship.

software_versions: Dict[str, str]

A mapping of other relevant software packages that are relevant to log for this dataset. Another example is the git tag or hash of a commit of a lab repository.

timestamp_end: Union[str, None] = None

Human-readable timestamp (ISO8601) as returned by datetime.datetime.now().astimezone().isoformat(). Specifies when the experiment/data acquisition ended.

timestamp_start: Union[str, None] = None

Human-readable timestamp (ISO8601) as returned by datetime.datetime.now().astimezone().isoformat(). Specifies when the experiment/data acquisition started.

tuid: Union[str, None] = None

The time-based unique identifier of the dataset. See quantify_core.data.types.TUID.

class QDatasetIntraRelationship(item_name=None, relation_type=None, related_names=<factory>, relation_metadata=<factory>)

A dataclass representing a dictionary that specifies a relationship between dataset variables.

A prominent example are calibration points contained within one variable or several variables that are necessary to interpret correctly the data of another variable.

See also

Relationship between primary and secondary variables

item_name: str | None = None

The name of the coordinate/variable to which we want to relate other coordinates/variables.

related_names: List[str]

A list of names related to the item_name.

relation_metadata: Dict[str, Any]

A free-form dictionary to store additional information relevant to this relationship.

relation_type: str | None = None

A string specifying the type of relationship.

Reserved relation types:

"calibration" - Specifies a list of main variables used as calibration data for the main variables whose name is specified by the item_name.

class QVarAttrs(unit='', long_name='', is_main_var=None, uniformly_spaced=None, grid=None, is_dataset_ref=False, has_repetitions=False, json_serialize_exclude=<factory>)

A dataclass representing the required attrs attribute of main and secondary variables.

See also

Required dataset data variables attributes

grid: bool | None = None

Indicates if the variables data are located on a grid, which does not need to be uniformly spaced along all dimensions. In other words, specifies if the corresponding main coordinates are the ‘unrolled’ points (also known as ‘unstacked’) corresponding to a grid.

If True than it is possible to use quantify_core.data.handling.to_gridded_dataset() to convert the variables to a ‘stacked’ version.

has_repetitions: bool = False

Indicates that the outermost dimension of this variable is a repetitions dimension. This attribute is intended to allow easy programmatic detection of such dimension. It can be used, for example, to average along this dimension before an automatic live plotting or analysis.

is_dataset_ref: bool = False

Flags if it is an array of quantify_core.data.types.TUID s of other dataset. See also Dataset for a “nested MeasurementControl” experiment.

is_main_var: bool | None = None

When set to True, flags this xarray data variable to correspond to a main variable, otherwise (False) it corresponds to a secondary variable.

json_serialize_exclude: List[str]

A list of strings corresponding to the names of other attributes that should not be json-serialized when writing the dataset to disk. Empty by default.

long_name: str = ''

A long name for this coordinate.

uniformly_spaced: bool | None = None

Indicates if the values are uniformly spaced. This does not apply to ‘true’ main variables but, because a MultiIndex is not supported yet by xarray when writing to disk, some coordinate variables have to be stored as main variables instead.

unit: str = ''

The units of the values.

_get_all_variables(dataset, var_type, is_main)

Shared internal logic used to retrieve variables/coordinates names.

Return type:

Tuple[List[str], List[str]]

_get_dims(dataset, main)

Return main or secondary dimensions.

Return type:

Tuple[List[str], List[str]]

get_main_coords(dataset)

Finds the main coordinates in the dataset (except secondary coordinates).

Finds the xarray coordinates in the dataset that have their attributes is_main_coord set to True (inside the xarray.DataArray.attrs dictionary).

Parameters:

dataset (Dataset) – The dataset to scan.

Return type:

List[str]

Returns:

str The names of the main coordinates.

get_main_dims(dataset)

Determines the ‘main’ dimensions in the dataset.

Each of the dimensions returned is the outermost dimension for an main coordinate/variable, OR the second one when a repetitions dimension is present. (see has_repetitions).

These dimensions are detected based on is_main_coord and is_main_var attributes.

Warning

The dimensions listed in this list should be considered “incompatible” in the sense that the main coordinate/variables must lie on one and only one of such dimension.

Note

The dimensions, on which the secondary coordinates/variables lie, are not included in this list. See also get_secondary_dims().

Parameters:

dataset (Dataset) – The dataset from which to extract the main dimensions.

Return type:

List[str]

Returns:

str The names of the main dimensions in the dataset.

get_main_vars(dataset)

Finds the main variables in the dataset (except secondary variables).

Finds the xarray data variables in the dataset that have their attributes is_main_var set to True (inside the xarray.DataArray.attrs dictionary).

Parameters:

dataset (Dataset) – The dataset to scan.

Return type:

List[str]

Returns:

str The names of the main variables.

get_secondary_coords(dataset)

Finds the secondary coordinates in the dataset.

Finds the xarray coordinates in the dataset that have their attributes is_main_coord set to False (inside the xarray.DataArray.attrs dictionary).

Parameters:

dataset (Dataset) – The dataset to scan.

Return type:

List[str]

Returns:

str The names of the secondary coordinates.

get_secondary_dims(dataset)

Returns the ‘main’ secondary dimensions.

For details see get_main_dims(), is_main_var and is_main_coord.

Parameters:

dataset (Dataset) – The dataset from which to extract the main dimensions.

Return type:

List[str]

Returns:

str The names of the ‘main’ dimensions of secondary coordinates/variables in the dataset.

get_secondary_vars(dataset)

Finds the secondary variables in the dataset.

Finds the xarray data variables in the dataset that have their attributes is_main_var set to False (inside the xarray.DataArray.attrs dictionary).

Parameters:

dataset (Dataset) – The dataset to scan.

Return type:

List[str]

Returns:

str The names of the secondary variables.

experiment

Utilities for managing experiment data.

class QuantifyExperiment(tuid, dataset=None)

Class which represents all data related to an experiment. This allows the user to run experiments and store data without the quantify_core.measurement.control.MeasurementControl. The class serves as an initial interface for other data storage backends.

__init__(tuid, dataset=None)

Creates an instance of the QuantifyExperiment.

Parameters:

• tuid (Optional[str]) – TUID to use

• dataset (default: None) – If the TUID is None, use the TUID from this dataset

_get_or_create_experiment_directory(name='')

Create the experiment directory containing the TUID set within the class, if it does not exist already.

To be used by methods that write/save. The experiment directory will be created on the first write/save, not before. Methods that load should not create an experiment directory.

name:

Readable name given to the datafile

Return type:

Path

Returns:

: The path to the experiment directory.

load_dataset()

Loads the quantify dataset associated with the TUID set within the class.

Return type:

Dataset

Returns:

:

Raises:

FileNotFoundError – If no file with a dataset can be found

load_metadata()

Loads the metadata from the directory specified by ~.experiment_directory.

Return type:

Dict[str, Any]

Returns:

: The loaded metadata from disk. None if no file is found.

Raises:

FileNotFoundError – If no file with metadata can be found

load_snapshot()

Loads the snapshot from the directory specified by ~.experiment_directory.

Return type:

Dict[str, Any]

Returns:

: The loaded snapshot from disk

Raises:

FileNotFoundError – If no file with a snapshot can be found

load_text(rel_path)

Loads a string from a text file from the path specified by ~.experiment_directory / rel_path.

Parameters:

rel_path (str) – path relative to the base directory of the experiment, e.g. “data.json” or “my_folder/data.txt”

Return type:

str

Returns:

: The loaded text from disk

Raises:

FileNotFoundError – If no file can be found at rel_path

save_metadata(metadata=None)

Writes the metadata to disk as specified by ~.experiment_directory.

Parameters:

metadata (Optional[Dict[str, Any]] (default: None)) – The metadata to be written to the directory

save_snapshot(snapshot=None)

Writes the snapshot to disk as specified by ~.experiment_directory.

Parameters:

snapshot (Optional[Dict[str, Any]] (default: None)) – The snapshot to be written to the directory

save_text(text, rel_path)

Saves a string to a text file in the path specified by ~.experiment_directory / rel_path.

Parameters:

• text (str) – text to be saved

• rel_path (str) – path relative to the base directory of the experiment, e.g. “data.json” or “my_folder/data.txt”

Return type:

None

write_dataset(dataset)

Writes the quantify dataset to the directory specified by ~.experiment_directory.

Parameters:

dataset (Dataset) – The dataset to be written to the directory

property experiment_directory: Path

Returns a path to the experiment directory containing the TUID set within the class.

Returns:

: