涡喷发动机建模中的gastab函数代码

涡喷发动机建模中的gastab函数代码如下：

def gastab(mach, alt):
    """
    Computes the gas properties for air as a function of altitude and Mach number.

    Parameters:
    -----------
    mach : float
        Mach number
    alt : float
        Altitude (m)

    Returns:
    --------
    gamma : float
        Specific heat ratio
    R : float
        Gas constant (J/kg-K)
    T : float
        Temperature (K)
    p : float
        Pressure (Pa)
    rho : float
        Density (kg/m^3)
    sos : float
        Speed of sound (m/s)
    """
    
    # Gas constants
    R0 = 287.05287  # J/kg-K
    g0 = 9.80665  # m/s^2
    gamma0 = 1.4

    # Temperature and pressure ratios
    T0 = 288.15  # K
    p0 = 101325  # Pa
    beta = 1 - 6.87535e-6*alt
    T = T0*beta
    p = p0*(beta**(g0/(R0*288.15)))
    rho = p/(R0*T)
    sos = np.sqrt(gamma0*R0*T)

    # Compute specific heat ratio and gas constant
    if mach < 1:
        gamma = gamma0
        R = R0
    else:
        gamma = gamma0*(1.0 - 0.5*(gamma0 - 1.0)*(mach**2 - 1.0)/(gamma0 + 1.0))
        R = R0/(1.0 + 0.5*(gamma0 - 1.0)*(mach**2 - 1.0)/(gamma0 + 1.0))

    return gamma, R, T, p, rho, sos

这个函数的作用是计算空气的气体属性，包括比热比、气体常数、温度、压力、密度和声速。它的输入参数为马赫数和海拔高度，输出为上述气体属性。