def compare_magnitude_along(self,
*args,
unit="SI",
data_list=[],
is_norm=False):
"""Returns the ndarrays of both fields interpolated in the same axes, using conversions and symmetries if needed.
Parameters
----------
self: Data
a Data object
*args: list of strings
List of axes requested by the user, their units and values (optional)
data_list: list
list of Data objects to compare
unit: str
Unit requested by the user ("SI" by default)
is_norm: bool
Boolean indicating if the field must be normalized (False by default)
Returns
-------
list of 1Darray of axis values, ndarrays of fields
"""
if data_list == []:
return self.get_magnitude_along(args, unit=unit, is_norm=is_norm)
else:
# Extract requested axes + field values
results = self.get_magnitude_along(args, unit=unit, is_norm=is_norm)
values = results.pop(self.symbol)
axes = results
data_axis_values = []
data_values = []
return_dict = {}
for data in data_list:
results = data.get_magnitude_along(args,
unit=unit,
is_norm=is_norm)
data_values.append(results.pop(data.symbol))
data_axis_values.append(results)
# Get the common bases
common_axis_values = {}
for axis in axes.keys():
common_axis_values[axis] = axes[axis]
for i, data in enumerate(data_list):
common_axis_values[axis] = get_common_base(
common_axis_values[axis], data_axis_values[i][axis])
# Interpolate over common axis values
values = get_interpolation(values, axes[axis],
common_axis_values[axis])
for i, data in enumerate(data_list):
data_values[i] = get_interpolation(
data_values[i],
data_axis_values[i][axis],
common_axis_values[axis],
)
return_dict[axis] = common_axis_values[axis]
# Return axis and values
return_dict[self.symbol] = values
for i, data in enumerate(data_list):
return_dict[data.symbol + "_" + str(i)] = data_values[i]
return return_dict
def get_axis(self, axis, normalizations):
"""Computes the vector 'axis' in the unit required, using conversions and symmetries if needed.
Parameters
----------
self: RequestedAxis
a RequestedAxis object
axis: Axis
an Axis object
normalizations: dict
dictionary of the normalizations
"""
# Get original values of the axis
if self.operation is not None:
module = import_module("SciDataTool.Functions.conversions")
func = getattr(module, self.operation) # Conversion function
values = array(func(axis.get_values()))
else:
values = array(axis.get_values())
# Unit conversions and normalizations
unit = self.unit
if unit == axis.unit or unit == "SI":
pass
elif unit in normalizations:
values = array([v / normalizations.get(unit) for v in values])
else:
values = convert(values, axis.unit, unit)
# Interpolate axis with input data
if self.extension == "whole":
self.values = values
elif self.input_data is not None:
self.input_data = get_common_base(self.input_data, values)
self.values = values
elif self.indices is not None:
self.values = values[self.indices]
def get_axis(self, axis):
"""Computes the vector 'axis' in the unit required, using conversions and symmetries if needed.
Parameters
----------
self: RequestedAxis
a RequestedAxis object
axis: Axis
an Axis object
"""
is_components = getattr(axis, "is_components", False)
if is_components:
values = axis.get_values()
self.extension = "list"
if self.indices is not None:
self.values = values[self.indices]
else:
self.values = values
else:
if self.extension == "smallestperiod":
is_smallestperiod = True
is_oneperiod = False
is_antiperiod = False
elif self.extension == "antiperiod":
is_smallestperiod = False
is_oneperiod = False
is_antiperiod = True
elif self.extension == "oneperiod" or self.transform == "fft":
is_smallestperiod = False
is_oneperiod = True
is_antiperiod = False
elif self.extension == "axis_data":
is_smallestperiod = True
is_oneperiod = False
is_antiperiod = False
else:
is_smallestperiod = False
is_oneperiod = False
is_antiperiod = False
# Get original values of the axis
if self.operation is not None:
module = import_module("SciDataTool.Functions.conversions")
func = getattr(module, self.operation) # Conversion function
values = array(
func(
axis.get_values(
is_oneperiod=is_oneperiod,
is_antiperiod=is_antiperiod,
is_smallestperiod=is_smallestperiod,
)
)
)
else:
values = array(
axis.get_values(
is_oneperiod=is_oneperiod,
is_antiperiod=is_antiperiod,
is_smallestperiod=is_smallestperiod,
)
)
# Unit conversions and normalizations
unit = self.unit
if unit == self.corr_unit or unit == "SI":
pass
elif unit in axis.normalizations:
values = array([v / axis.normalizations.get(unit) for v in values])
else:
values = convert(values, self.corr_unit, unit)
# Rebuild symmetries in fft case
if self.transform == "fft":
if "period" in axis.symmetries:
if axis.name != "time":
values = values * axis.symmetries["period"]
elif "antiperiod" in axis.symmetries:
if axis.name != "time":
values = (
values * axis.symmetries["antiperiod"] / 2
)
# Interpolate axis with input data
if self.extension in ["whole", "oneperiod", "antiperiod", "smallestperiod"]:
self.values = values
elif self.input_data is not None:
if len(self.input_data) == 2 and self.extension != "axis_data":
self.indices = [
i
for i, x in enumerate(values)
if x >= self.input_data[0] and x <= self.input_data[-1]
]
self.input_data = None
else:
if self.extension == "axis_data":
self.input_data = get_common_base(self.input_data, values, is_downsample=True)
else:
self.input_data = get_common_base(self.input_data, values)
self.values = values
if self.indices is not None:
self.values = values[self.indices]
def get_harmonics(self,
N_harm,
*args,
unit="SI",
is_norm=False,
is_flat=False):
"""Returns the complex Fourier Transform of the field, using conversions and symmetries if needed.
Parameters
----------
self: Data
a Data object
N_harm: int
Number of largest harmonics to be extracted
args: list
Axes names, ranges and units
unit: str
Unit demanded by the user ("SI" by default)
is_norm: bool
Boolean indicating if the field must be normalized (False by default)
is_flat: bool
Boolean if the output data remains flattened (for 2D cases)
Returns
-------
list of 1Darray of axes values, ndarray of magnitude of FT
"""
# Read the axes input in args
if len(args) == 1 and type(args[0]) == tuple:
args = args[0] # if called from another script with *args
axes_list = read_input_strings(args, [])
# Extract the requested axes (symmetries + unit)
for axis_requested in axes_list:
if axis_requested[3] == "values":
# Get original values of the axis
axis_requested.append(
self.get_FT_axis(axis_requested[0] + axis_requested[1]))
# Interpolate axis with input data
if str(axis_requested[4]) == "whole":
axis_requested[4] = axis_requested[5]
axis_requested[5] = "whole"
else:
axis_requested[4] = get_common_base(axis_requested[5],
axis_requested[4])
# Change fft name for the slices of the field
if axis_requested[0] == "freqs":
axis_requested[0] = "time"
elif axis_requested[0] == "wavenumber":
axis_requested[0] = "angle"
# Check if the requested axis is defined in the Data object
for axis_requested in axes_list:
axis_name = axis_requested[0]
is_match = False
for index, axis in enumerate(self.axes):
if axis.name == axis_name:
is_match = True
if not is_match:
axes_list.remove(axis_requested)
# Rebuild symmetries of field if axis is extracted
values = self.values
for index, axis in enumerate(self.axes):
for axis_requested in axes_list:
if axis.name in self.symmetries.keys(
) and axis.name == axis_requested[0]:
values = rebuild_symmetries(values, index,
self.symmetries.get(axis.name))
# Extract the slices of the field (single values)
for index, axis in enumerate(self.axes):
is_match = False
for axis_requested in axes_list:
if axis.name == axis_requested[0]:
is_match = True
if axis_requested[3] == "indices" and axis_requested[
2] == "single":
values = take(values, axis_requested[4], axis=index)
if not is_match: # Axis was not specified -> take slice at the first value
values = take(values, [0], axis=index)
# Interpolate over axis values (single values)
for index, axis in enumerate(self.axes):
for axis_requested in axes_list:
if (axis.name == axis_requested[0]
and axis_requested[3] == "values"
and axis_requested[2] == "single"):
values = apply_along_axis(
get_interpolation,
index,
values,
axis_requested[5],
axis_requested[4],
)
# Perform Fourier Transform
values = np_abs(comp_fft(values))
# Extract slices again (intervals)
for index, axis in enumerate(self.axes):
for axis_requested in axes_list:
if axis.name == axis_requested[0]:
if axis_requested[2] == "indices" and axis_requested[
2] == "interval":
values = take(values, axis_requested[4], axis=index)
# Interpolate over axis values again (intervals)
for index, axis in enumerate(self.axes):
for axis_requested in axes_list:
if axis.name == axis_requested[0]:
if axis_requested[3] == "values" and axis_requested[
2] == "interval":
values = apply_along_axis(
get_interpolation,
index,
values,
axis_requested[5],
axis_requested[4],
)
# Eliminate dimensions=1
values = squeeze(values)
# Test if data is 1D or 2D
if len(values.shape) > 2:
raise AxisError("ERROR: only 1D or 2D implemented")
else:
# Convert into right unit
if unit == self.unit or unit == "SI":
if is_norm:
try:
values = values / self.normalizations.get("ref")
except:
raise NormError(
"ERROR: Reference value not specified for normalization"
)
elif unit == "dB":
ref_value = 1.0
if "ref" in self.normalizations.keys():
ref_value *= self.normalizations.get("ref")
values = to_dB(values, self.unit, ref_value)
elif unit == "dBA":
ref_value = 1.0
is_match = False
if "ref" in self.normalizations.keys():
ref_value *= self.normalizations.get("ref")
for axis_requested in axes_list:
if axis_requested[0] == "time":
is_match = True
values = to_dBA(values, axis_requested[4], self.unit,
ref_value)
if not is_match:
raise UnitError(
"ERROR: dBA conversion only available for fft with frequencies"
)
elif unit in self.normalizations:
values = values / self.normalizations.get(unit)
else:
values = convert(values, self.unit, unit)
# 1D case
if len(values.shape) == 1:
for axis_requested in axes_list:
if axis_requested[2] == "interval":
axis_values = axis_requested[4]
indices = argsort(negative(values))
indices = indices[:N_harm]
axis_values = axis_values[indices]
values = values[indices]
return [axis_values, values]
# 2D case
else:
for axis_requested in axes_list:
if axis_requested[0] == "angle":
r = axis_requested[4]
elif axis_requested[0] == "time":
f = axis_requested[4]
# Flatten the data
values_flat = values.flatten()
R, F = meshgrid(r, f)
f = F.flatten()
r = R.flatten()
# Get the N_harm largest peaks
indices = argsort(negative(values_flat))
indices = indices[:N_harm]
values = values_flat[indices]
f = f[indices]
r = r[indices]
if len(values.shape) == 2 and not is_flat:
f.reshape((N_harm, N_harm))
r.reshape((N_harm, N_harm))
values.reshape((N_harm, N_harm))
return [f, r, values]