gamma-simulator 1.0.4

a gamma simulator

Gamma_simulator

This is a gamma pulse simulator jointly developed by Shamoon College of Engineering(SCE) in Israel and Shanghai Advanced Research Institute in China.Here we will give a brief introduction to our software, including the what and why. For more specific implementation steps of the software, please refer to our paper. Of course,if you are a pure user, please jump directly to Use to see how to use it.For any questions about the software, you can leave a message or send an email to me, I will reply as soon as possilble

Introduction

What is Gamma Simulator?

Gamma simulator is a gamma pulse simulator with parameter customization function, you can specify the type of radioactive source and pulse count rate and other characteristics, generate pulse signals that meet the corresponding characteristics

Why do we creat it?

The original intention of the gamma simulator was to introduce deep learning into energy spectroscopy in the later stage. The use of deep learning to process pulse signals requires that the collected pulse signals have corresponding labels, which is impossible in commercial energy spectrometer. Therefore, we used the simulator to label the pulse signals while generating them, so as to facilitate the reference of deep learning methods. At the same time, simulators can greatly reduce the manpower, material and financial resources of the signal collection process, and can be used to preliminarily test signal processing methods

Software structure

Macrostructure

Implementation structure

Parameter description

Setting Parameters:

Parameter name	Parameter description
verbose	Whether to output detailed information
verbose_plots	Whether images need to be output
source	The simulated radioactive source
signal_len	Length of time to simulate sampling(s)
fs	Analog sampling rate
lambda_value	Analog pulse count rate(cps)
dict_type	Shape type model of the simulated pulse
dict_shape_params	dict shape params
noise_unit	Unit of noise
noise	The magnitude of noise in the given unit
dict_size	Shape dictionary size due to jitter
seed	The simulated random number seed

Shape parameters:

Parameter name	Parameter description
t_rise	rise time of the shape
t_fall	fall time of the shape
shape_len	length of the shape in samples
shape_len_sec	length of the shape in seconds

Events parameters:

Parameter name	Parameter description
n_events	number of events in the signal
times	arrival times of the events
energies	energy values for each event
lambda_measured	actual event rate
shape_param1, shape_param2	shape parameters for each event

Signal parameters:

Parameter name	Parameter description
signal_len	length of the signal in samples
signal_len_sec	length of the signal in seconds
duty_cycle	duty cycle of the signal
pile_up_stat	number of the pile-ups in the generated signal
measured_snr	measured SNR of the generated signal (dB)

Use

Install

Make sure you have the following libraries in your environment

• numpy
• scipy
• matplotlib
• urllib
  You can use the following command to install the libaries

pip install numpy scipy matplotlib urllib

Import

from gamma_simulator import gamma_simulator

Run

Step 1.Creat an instance

simulator = gamma_simulator()

Step 2.Define parameters

simulator = gamma_simulator(verbose=True,
                            verbose_plots={'shapes': True, 'signal': True},
                            source={'name': 'Co-60', 'weights': 1},
                            signal_len=1,  # "analog" signal of 1 second that are 1e7 samples
                            fs=10e5,
                            lambda_value=1e4,
                            dict_type='gamma',
                            dict_shape_params={'mean1':  1.1,
                                               'std1': 0.001,
                                               'mean2': 1e5,
                                               'std2': 1e3},
                            noise_unit='std',
                            noise=1e-3,
                            dict_size=10,
                            seed=42)

Step 3.Creat the signal

signal = simulator.generate_signal()

Notice

Shape parameter

If you are not familiar with shape parameters, use the following combination of parameters

{dict_type='gamma',
dict_shape_params={'mean1':  1.1,
'std1': 0.001,
'mean2': 1e5,
'std2': 1e3}

or

{dict_type='double_exponential',
dict_shape_params={'mean1': 1e-7, 
'std1': 1e-9,
'mean2': 1e-5,
'std2': 1e-7}

Plot setting

Our simulator supports drawing a variety of graphs, including energy, shape, signal and spectrum.

• Energy：Ideal energy spectrum of the drawn signal source (simulator built-in database)
• Shape：Draws a dictionary set of all possible signal shapes
• Signal：When the length of the resulting signal is less than 2000, the generated signal is drawn, and when the length is greater than 2000, the first 2000 sampling points are drawn

The default option is not to draw, if you need to draw, you need to change the specified value in the parameter definition to True

verbose_plots={'energy':True, 'shapes': True, 'signal': True}

Examples

from gamma_simulator import gamma_simulator
simulator = gamma_simulator(verbose=True,
                            verbose_plots={'shapes': True, 'signal': True},
                            source={'name': 'Co-60', 'weights': 1},
                            signal_len=1,  # "analog" signal of 1 second that are 1e7 samples
                            fs=10e6,
                            lambda_value=1e4,
                            dict_type='double_exponential',
                            dict_shape_params={'mean1': 1e-7,  # continuous-time parameters measured in seconds
                                               'std1': 1e-9,
                                               'mean2': 1e-5,
                                               'std2': 1e-7},
                            noise_unit='std',
                            noise=1e-3,
                            dict_size=10,
                            seed=42)
signal = simulator.generate_signal()

from gamma_simulator import gamma_simulator
simulator = gamma_simulator(verbose=True,
                            verbose_plots={'energy': True, 'signal': True},
                            source={'name': ['Co-60', 'I-125'], 'weights': [1, 2]},
                            signal_len=1,  # "analog" signal of 1 second that are 1e7 samples
                            fs=10e6,
                            lambda_value=1e4,
                            dict_type='gamma',
                            dict_shape_params={'mean1':  1.1,  # continuous-time parameters measured in seconds
                                               'std1': 0.001,
                                               'mean2': 1e5,
                                               'std2': 1e3},
                            noise_unit='std',
                            noise=1e-3,
                            dict_size=10,
                            seed=42)
signal = simulator.generate_signal()

version

1.0.1 upload to pypi

1.0.2 add license and install_requires

1.0.3 can't import

1.0.4 successfully import and fix some bug about gamma.pdf and gamma.ppf parameters