blackscholes_cuda.py 文件源码

def black_scholes_cuda_kernel(callResult, putResult, S, X,
                       T, R, V):
    #    S = stockPrice
    #    X = optionStrike
    #    T = optionYears
    #    R = Riskfree
    #    V = Volatility
    i = cuda.threadIdx.x + cuda.blockIdx.x * cuda.blockDim.x
    if i >= S.shape[0]:
        return
    sqrtT = math.sqrt(T[i])
    d1 = (math.log(S[i] / X[i]) + (R + 0.5 * V * V) * T[i]) / (V * sqrtT)
    d2 = d1 - V * sqrtT
    cndd1 = cnd_cuda(d1)
    cndd2 = cnd_cuda(d2)

    expRT = math.exp((-1. * R) * T[i])
    callResult[i] = (S[i] * cndd1 - X[i] * expRT * cndd2)
    putResult[i] = (X[i] * expRT * (1.0 - cndd2) - S[i] * (1.0 - cndd1))