Table of Contents
Name | Direction | Type | Default | Description |
---|---|---|---|---|
InputWorkspace | Input | MatrixWorkspace | Mandatory | The name of the input 2D workspace. |
OutputWorkspace | Output | MatrixWorkspace | Mandatory | The name of the output 2D workspace. |
ApodizationFunction | Input | string | None | The apodization function to apply to the data. Allowed values: [‘None’, ‘Lorentz’, ‘Gaussian’] |
DecayConstant | Input | number | 1.5 | The decay constant for the apodization function. |
Padding | Input | number | 0 | The amount of padding to add to the data,it is the number of multiples of the data set.i.e 0 means no padding and 1 will double the number of data points. |
NegativePadding | Input | boolean | False | If true padding is added to both sides of the original data. Both sides share the padding |
Padding is when the input data is extended by adding extra measurments of zero at regular intervals. For real data this is only done after the end of the input data. However, for complex data the padding should be shared between the start and end of the input data.
Apodization functions can be used to remove data with large errors. These are usualy found at large time scales. These take a decay constant ( ) that determines the rate at which the data goes to zero. The time the function is evaluated at is denoted by . The current implementation includes the following functions:
Example - Apply apodization function:
import math
import numpy as np
y = [100, 150, 50, 10, 5]
x = [1,2,3,4,5,6]
input = CreateWorkspace(x,y)
output=PaddingAndApodization(InputWorkspace=input,ApodizationFunction="Gaussian",DecayConstant=2.44,Padding=0,)
print("output: {}".format(['{0:.2f}'.format(value) for value in output.readY(0)]))
Output:
output: ['91.94', '107.20', '23.48', '2.61', '0.61']
Example - Add padding:
import math
import numpy as np
y = [100, 150, 50, 10, 5]
x = [1,2,3,4,5,6]
input = CreateWorkspace(x,y)
output=PaddingAndApodization(InputWorkspace=input,Padding=2,)
print("output: {}".format(['{0:.2f}'.format(value) for value in output.readY(0)]))
Output:
output: ['100.00', '150.00', '50.00', '10.00', '5.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00']
Example - Add padding and apodization function:
import math
import numpy as np
y = [100, 150, 50, 10, 5]
x = [1,2,3,4,5,6]
input = CreateWorkspace(x,y)
output=PaddingAndApodization(InputWorkspace=input,ApodizationFunction="Gaussian",DecayConstant=2.44,Padding=2,)
print("output: {}".format(['{0:.2f}'.format(value) for value in output.readY(0)]))
Output:
output: ['91.94', '107.20', '23.48', '2.61', '0.61', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00', '0.00']
Categories: Algorithms | Arithmetic\FFT
C++ source: PaddingAndApodization.cpp (last modified: 2017-09-14)
C++ header: PaddingAndApodization.h (last modified: 2017-09-11)