howoo0808

摘要： def calculate_monthly_payment(P, annual_interest_rate, n_years): monthly_interest_rate = annual_interest_rate / 12 / 100 total_months = n_years * 12 M 阅读全文

摘要： 有四个年龄组的鱼。该鱼类在每年后4个月季节性集中产卵繁殖。按规定，捕捞作业只允许在前8个月进行，每年投入的捕捞能力固定不变。单位时间捕捞量鱼各年龄组鱼群条数的比例称为捕捞强度系。使用只能捕捞3、4龄鱼的13mm网眼的拉网，其两个捕捞强度系数比为0.42：1。各年龄组鱼的自然死亡率为0.8（1/年）， 阅读全文

摘要： 程序文件ex8_8.py from scipy.integrate import odeint import numpy as np import pylab as plt yx = lambda y,x: [y[1], np.sqrt(1+y[1]**2)/5/(1-x)] x0 = np.ara 阅读全文

摘要： 程序文件ex8_7.py from scipy.integrate import odeint import numpy as np import pylab as plt import sympy as sp dy = lambda y, x: -2y+2x2+2x #自变量在后面 xx = np 阅读全文

摘要： 程序文件ex8_6.py import sympy as sp sp.var('t') sp.var('x1:4', cls=sp.Function) #定义3个符号函数 x = sp.Matrix([x1(t), x2(t), x3(t)]) #列向量 A = sp.Matrix([[3,-1,1 阅读全文

摘要： 程序文件ex8_5.py import sympy as sp sp.var('t'); y=sp.Function('y') u=sp.exp(-t)sp.cos(t) eq=y(t).diff(t,4)+10y(t).diff(t,3)+35y(t).diff(t,2)+ 50y(t).diff 阅读全文

摘要： 程序文件ex8_4.py import sympy as sp sp.var('x'); y=sp.Function('y') eq=y(x).diff(x,2)-2*y(x).diff(x)+y(x)-sp.exp(x) con={y(0): 1, y(x).diff(x).subs(x,0): 阅读全文

摘要： 程序文件ex8_3.py import sympy as sp sp.var('x'); y=sp.Function('y') eq=y(x).diff(x)+2y(x)-2x**2-2*x s=sp.dsolve(eq, ics={y(0):1}) s=sp.simplify(s); print( 阅读全文

摘要： import numpy as np import matplotlib.pyplot as plt from scipy.integrate import solve_ivp def model(t, y): f, df_dm, d2f_dm2, T, dT_dm = y d3f_dm3 = -3 阅读全文

摘要： import numpy as np import matplotlib.pyplot as plt from scipy.integrate import solve_ivp def system(t, state): x, y = state dxdt = -x3 - y dydt = x - 阅读全文

摘要： import numpy as np import pandas as pd import matplotlib.pyplot as plt from scipy.interpolate import interp1d, PchipInterpolator, CubicSpline from sci 阅读全文

摘要： import numpy as np import matplotlib.pyplot as plt from scipy.optimize import curve_fit, leastsq, least_squares from scipy.constants import e def g(x, 阅读全文

摘要： import numpy as np import scipy.interpolate as spi import scipy.integrate as spi_integrate def g(x): return ((3x**2 + 4x + 6) * np.sin(x)) / (x**2 + 8 阅读全文

摘要： 程序文件ex7_4.py import numpy as np from scipy.interpolate import interp1d from scipy.interpolate import lagrange import pylab as plt a = np.loadtxt('data 阅读全文

摘要： 程序文件ex7_3.py import numpy as np import pylab as plt from scipy.interpolate import lagrange yx = lambda x: 1/(1+x**2) def fun(n): x = np.linspace(-5, 5 阅读全文

摘要： import numpy as np import matplotlib.pyplot as plt from scipy.interpolate import griddata def f(x, y): return (x2 - 2*x) * np.exp(-x2 - y**2 - x*y) x_ 阅读全文

摘要： import numpy as np import matplotlib.pyplot as plt from scipy.interpolate import interp1d, CubicSpline T = np.array([700, 720, 740, 760, 780]) V = np. 阅读全文

摘要： 用python绘制一个无向图：v1在中间，v2、v3、v4、v5、v6在周围；v1与v2、v3、v4相连；v2与v3、v6、v1相连；v3与v1、v2、v4相连；v4与v1、v3、v5相连；v5与v4、v6相连；v6与v2、v5相连 点击查看代码 import networkx as nx impo 阅读全文

摘要： 点击查看代码 import numpy as np matches = np.array([ [0, 1, 0, 1, 1, 1], # 1队 [0, 0, 0, 1, 1, 1], # 2队 [1, 1, 0, 1, 0, 0], # 3队 [0, 0, 0, 0, 1, 1], # 4队 [0, 阅读全文

摘要： 点击查看代码 import numpy as np distances = np.array([ [0, 2, 7, np.inf, np.inf, np.inf], [2, 0, 4, 6, 8, np.inf], [7, 4, 0, 1, 3, np.inf], [np.inf, 6, 1, 0 阅读全文