kernels.py 文件源码

def getTrainKernel(self, params):
        self.checkParams(params)
        if (self.sameParams(params)): return self.cache['getTrainKernel']
        if ('K_sq_scaled' not in self.cache.keys()): self.cache['K_sq_scaled'] = [None for i in xrange(self.getNumParams())]

        ell = np.exp(params)
        K = 0
        for i in xrange(self.getNumParams()):
            if (self.sameParams(params, i)): K += self.cache['K_sq_scaled'][i]
            else:
                self.cache['K_sq_scaled'][i] = self.K_sq[i] / ell[i]**2
                K += self.cache['K_sq_scaled'][i]
        K_exp = np.exp(-K / 2.0)
        self.cache['getTrainKernel'] = K_exp
        self.saveParams(params)
        return K_exp