flap.coordinate

Created on Wed Jan 23 09:44:50 2019

This is the coordinate description and related methods for FLAP

@author: Sandor Zoletnik (zoletnik.sandor@ek-cer.hu) Centre for Energy Research

class flap.coordinate.Coordinate(name=None, unit=None, mode=<flap.coordinate.CoordinateMode object>, shape=[], start=None, step=None, c_range=None, values=None, value_index=None, value_ranges=None, dimension_list=[])

Bases: object

Class for the description of a mapping of coordinate values from an n-dimensional coordinate sample space to coordinates of an m-dimensional data matrix.

The coordinate sample space is a rectangular equidistant point matrix, with equal steps in each dimension. For dimension i, the sample index spans 0 ... n-1 if shape[i] == n.

The sample space in this coordinate description does not necessarily match the shape of any sub-matrix of the data object. If the shape is different then interpolation is done assuming the coordinate of the first(last) point of the coordinate matrix is the coordinate of the first(last) data point.

A coordinate can be anything described by name and unit. Standard coordinates: ‘Time’, ‘Channel’, ‘Channel number’, ‘Device_x’, ‘Device_y’, ‘Device_z’, ‘Device_R’, ‘Device_Z’, ‘Device_phi’, ‘Flux_r’, ‘Flux_theta’, ‘Flux_phi’, ‘Frequency’, ‘Time lag’.

The ranges and start-step pair of parameters are alternatives.

Parameters:

namestr, optional, default=None

Name of the quantity measured in the coordinate. (E.g. ‘Time’.)

unitstr, optional, default=None

Name of the unit used along the coordinate. (E.g. ‘Second’.)

modeflap.CoordinateMode, optional, default=``CoordinateMode()``

Coordinate mode to use.

shapearray_like, optional, default=``[]``

The shape of the sample space matrix in this coordinate description. If len(shape) == 0, then the coordinate is the same for all samples and it is described by values and value_ranges. The parameter shape should not have a 1 element. In the equidistant case only the dimension of shape is used.

startfloat, optional, default=None

Start of the coordinate mapping. Only valid if the coordinate mode is equidistant.

steplist of float, optional, default=None

Steps of the coordinate mapping. One-dimensional list with the same number of elements as dimension_list. Only valid if the coordinate mode is equidistant.

c_rangearray_like, optional, default=None

Used for specifying a range when reading data.

values, value_indexarray_like, optional, default=None

Only valid if the coordinate mode is non-equidistant. The values describe the coordinate values at value_index. Sample values are a 2D array of size (len(shape), N_sample) containing indices to the coordinate matrix described by shape. That is, values_index[:,i] gives the coordinates of values[i] in the coordinate sample space.

value_rangesfloat | array_like | dict, optional, default=None

Specifies the range around the coordinate values.

If the coordinate mode has symmetric ranges, it is symmetric around the values: [values-value_ranges, value+value_ranges]. If not symmetric, it is [values-value_ranges_low, value+value_ranges_high].

For equidistant coordinates:

• if the range is not symmetric, value_ranges should be a 2 element array;

• if the range is symmetric, value_ranges should be a scalar.

For non-equidistant coordinates:

• if the range is not symmetric, value_ranges should be a dictionary with keys ‘low’, ‘high’, with each value having the same dimensions as values;

• if the range is symmetric, value_ranges should have the same shape as values.

dimension_listlist, optional, default=[]

List of data dimensions with which this coordinate is associated (0…). Length of dimension_list should be equal to length of shape.

change_dimensions()

Return the list of dimensions of the data array along which this coordinate changes.

Returns:

list

data(data_shape=None, index=None, options=None)

Return the coordinates, low and high limits for a sub-array of the data array in a DataObject.

Parameters:

data_shapearray_like, optional, default=None

The shape of the data array (without slicing) for which coordinates are requested.

indexlist | tuple of int, optional, default=None

Describes the elements in DataObject.data for which the coordinates are required. The length of the array should be identical to the number of dimensions of the data array. Elements can be a mixture of numbers, slice objects, lists, numpy arrays, integer iterators and ellipses.

Examples for 3D array:

• (...,0,0): coordinates of the elements in the first row of the data array

• (slice(2,5),2,...)

optionsdict, optional, default=None

Dictionary with options for processing:

• ‘Interpolation’ (default=’Linear’):

  • ‘Linear’: For non-equidistant axis, when values shape is different from data shape)

• ‘Change only’ (default=False):

  • True (return only the data for those dimensions where this coordinate changes. E.g. if it changes only along one dimension the output array will have 1 element in all other dimensions.)

Returns:

values, value_range_low, value range_higharray_like

Values and the respective low and high range values. The low and high values are the absolute values not, the difference from values.

data_range(data_shape=None)

Return the data range and the data range with errors for the coordinate.

Parameters:

data_shapearray_like, optional, default=None

Data shape.

Returns:

value_range, value_range_errorlist

property dimension_list

List of data dimensions with which this coordinate is associated with.

Returns:

list of int

dtype()

Return the data type of the coordinate.

Return standard Python types: str, int, float, complex, boolean or object.

Returns:

type

isnumeric()

Return whether the data type is numeric.

Returns:

bool

nochange_dimensions(data_shape)

Return the list of dimensions of the data array along which this coordinate does not change.

Parameters:

data_shapearray_like

The data shape to use.

Returns:

list

non_interpol(data_shape)

Return True if the shape of the coordinate description is the same as the sub-data-array for which it applies and self.value_index is None. In this case there is no need for interpolation, coordinate values are copied. Valid only for non-equidistant coordinate mode.

Parameters:

data_shapearray_like

The shape of the sub-data-array.

Returns:

bool

property shape

The shape of the sample space matrix in this coordinate description.

Returns:

list

property start

Start of the coordinate mapping. Only valid if the coordinate mode is equidistant.

Returns:

float or None

property step

Steps of the coordinate mapping. Only valid if the coordinate mode is equidistant.

Returns:

list or None

string_subtype()

Return the type of the values if the coordinate type is str. Otherwise returns None.

Returns:

type or None

class flap.coordinate.CoordinateMode(equidistant=True, range_symmetric=True)

Bases: object

Class for storing mode flags of the coordinate description.

Parameters:

equidistantbool, optional, default=True

Whether the coordinate values are equidistant.

range_symmetricbool, optional, default=True

Whether the ranges corresponding to the coordinates are symmetric.

class flap.coordinate.Intervals(start, stop, step=None, number=None)

Bases: object

Class to describe a series of intervals.

Different types of intervals exist:

• Regular intervals are identical length ones repeating with a fixed step.

• Irregulars are just a list of start-stop values.

• For integer type values both the start and stop value is included.

• The optional number gives the number of ranges for the regular intervals.

Parameters:

start, stopint | float | ndarray

For regular intervals: start and stop value of first interval. For irregular intervals: start and stop value of all intervals. (Identical-length numpy arrays.)

stepint | float, optional, default=None

If not given, the intervals are assumed to be irregular, otherwise regular.

numberint, optional, default=None

The number of intervals in regular case. If not set, the intervals continue indefinitely.

interval_limits(limits=None, partial_intervals=False)

Return the range lower and upper limits as two numpy arrays. Limit the ranges within argument limits.

Parameters:

limitsarray_like, optional, default=None

Two-element list with lower and upper limit, in this order.

partial_intervalsbool, optional, default=False

Return also partial ranges which extend over limits. Their size will be truncated.

Returns:

range_starts, range_stopsndarray

The range lower and upper limits.

interval_number(limits=None, partial_intervals=False)

Return the number of intervals and the index of the start interval. Limit the ranges within argument limits.

Parameters:

limitsarray_like, optional, default=None

2 elements list with lower and upper limit.

partial_intervalsbool, optional, default=False

Take into account also partial ranges which extend over limits.

Returns:

int

The number of intervals.

int

The index of the start interval.

regular()

Return True if the interval is regular, otherwise returns False.

Returns:

bool

class flap.coordinate.Unit(name='', unit='')

Bases: object

Class representing the unit of a quantity.

Parameters:

namestr, optional, default=’’

Name of the quantity. (E.g. ‘Time’.)

unitstr, optional, default=’’

Name of the unit. (E.g. ‘Second’.)

title(language='EN', complex_txt=None, new_unit=None)

Return a title string to be used in plotting.

Parameters:

language{‘EN’, ‘HU’}, optional, default=’EN’

Language to be used for creating the title string.

complex_txt{[0, 0], [0, 1], [1, 0], [1, 1]}, optional, default=None

List of 2 numbers representing which component of a complex variable is used:

• [0,0]: Amplitude

• [0,1]: Phase

• [1,0]: Real

• [1,1]: Imaginary

new_unitstr, optional, default=None

Unit string override to be used instead of self.unit.

Returns:

str

The title string.