标签：none python应用 ide def 函数 spl bsp isp inf
CsI 闪烁体晶体+PD+前放输出信号满足：
$U(t) = \frac{N_f\tau_p}{\tau_p-\tau_f} \left[ e^{-\frac{t}{\tau_p}}-e^{-\frac{t}{\tau_f}} \right] + \frac{N_s\tau_p}{\tau_p-\tau_s} \left[ e^{-\frac{t}{\tau_p}}-e^{-\frac{t}{\tau_s}} \right] $
其中，U(t) 表示信号输出，电压单位，N 表示闪烁体晶体发出的光中快慢成分的强度，$\tau$ 表示快慢成分的衰减时间，$\tau_p$ 表示前放衰减时间，即前放 RC 常数。
现已有 U(t) 数据，需要拟合给出快慢成分的衰减时间 $\tau$。
# -*- coding: utf-8 -*- """ Created on Mon Jun 15 15:28:17 2020 @author: kurrrr """ import numpy as np import matplotlib.pyplot as plt from scipy.optimize import curve_fit ‘‘‘ t_pre : preamplifier tau b: number of fast photons c: number of slow photons p: tau of fast photons q: tau of slow photons u: x offset v: y offset ‘‘‘ t_pre = 26.0 def pre_func_1(x, v): return v def pre_func_2(x, b, c, p, q, u, v): global t_pre return (b*t_pre/(t_pre-p) * (np.exp(-(x-u)/t_pre)-np.exp(-(x-u)/p)) + c*t_pre/(t_pre-q) * (np.exp(-(x-u)/t_pre)-np.exp(-(x-u)/q)) + v) def pre_func(x, b, c, p, q, u, v): return np.piecewise(x, [x < u, x >= u], [lambda x: pre_func_1(x, v), lambda x: pre_func_2(x, b, c, p, q, u, v)]) alpha_file = open("./gamma_csi.txt", "r") data_str = alpha_file.read() data_str = data_str.split() data = list(map(float, data_str)) x = data[0::2] y = data[1::2] popt, pcov = curve_fit(pre_func, x, y, [0.6, 1.2, 1, 1, 2, 0], maxfev=5000) print(popt) plt.scatter(x, y, marker=‘.‘, label="original data") y_fit = ([pre_func(xx, popt[0], popt[1], popt[2], popt[3], popt[4], popt[5]) for xx in x]) plt.plot(x, y_fit, label="Fitted Curve", color=‘red‘) plt.legend(loc=‘upper right‘) plt.show() # show the fit result p_str = "Tf = " + str(min(popt[2], popt[3])+0.0005)[:5] q_str = "Ts = " + str(max(popt[2], popt[3])+0.0005)[:5] plt.text(60, 0.8, "fit result", fontdict={‘size‘: 16, ‘color‘: ‘b‘}) plt.text(60, 0.7, p_str, fontdict={‘size‘: 16, ‘color‘: ‘b‘}) plt.text(60, 0.6, q_str, fontdict={‘size‘: 16, ‘color‘: ‘b‘})
$\alpha$ 信号拟合结果：
$\gamma$ 信号拟合结果：
标签：none python应用 ide def 函数 spl bsp isp inf
原文地址：https://www.cnblogs.com/kurrrr/p/13130986.html
