def sample(self):

        """
        Method to pick the sample satisfying the likelihood constraint using uniform sampling

        Returns
        -------
        new : object
            The evolved sample
        number : int
            Number of likelihood calculations after sampling

        """

        new = Source()

        x_l, x_u = self.getPrior_X()
        y_l, y_u = self.getPrior_Y()
        r_l, r_u = self.getPrior_R()
        a_l, a_u = self.getPrior_A()

        while(True):

            new.X = np.random.uniform(x_l,x_u)
            new.Y = np.random.uniform(y_l,y_u)
            new.A = np.random.uniform(a_l,a_u)
            new.R = np.random.uniform(r_l,r_u)
            new.logL = self.log_likelihood(new)
            self.number+=1

            if(new.logL > self.LC):
                break

        return new, self.number
Exemple #2
0
    def sample(self):
        """
        Method to pick the sample satisfying the likelihood constraint using uniform sampling

        Returns
        -------
        new : object
            The evolved sample
        number : int
            Number of likelihood calculations after sampling

        """

        new = Source()

        x_l, x_u = self.getPrior_X()
        y_l, y_u = self.getPrior_Y()
        r_l, r_u = self.getPrior_R()
        a_l, a_u = self.getPrior_A()

        while (True):

            new.X = np.random.uniform(x_l, x_u)
            new.Y = np.random.uniform(y_l, y_u)
            new.A = np.random.uniform(a_l, a_u)
            new.R = np.random.uniform(r_l, r_u)
            new.logL = self.log_likelihood(new)
            self.number += 1

            if (new.logL > self.LC):
                break

        return new, self.number
Exemple #3
0
    def sample_source(self):
        """
        Sampling the object from prior distribution.

        Returns
        -------
        src : object
            The source object with X,Y,A,R sampled from their prior distribution and log likelihood calculated.


        """

        src = Source()
        src.X = random.uniform(0.0, self.x_upper)
        src.Y = random.uniform(0.0, self.y_upper)
        src.A = random.uniform(self.amplitude_lower, self.amplitude_upper)
        src.R = random.uniform(self.R_lower, self.R_upper)
        src.logL = self.log_likelihood(src)
        return src
Exemple #4
0
    def sample(self):
        """
        Sampling from the built ellipsoids.

        Returns
        -------
        clust : object
            The sampled point satisfying the likelihood constraint
        number : int
            The number of likelihood calculations until this

        """

        trial = Source()
        clust = Source()
        z = int(np.random.uniform(0, len(self.ellipsoid_set)))
        points = None
        try:
            points = self.ellipsoid_set[z].sample(n_points=50)
        except IndexError:
            raise Exception(
                "Adjust clustering parameters or number of active samples")
        max_likelihood = self.LC
        count = 0
        r_l, r_u = self.getPrior_R()
        a_l, a_u = self.getPrior_A()
        while count < 50:
            trial.X = points[count][0]
            trial.Y = points[count][1]
            trial.A = np.random.uniform(a_l, a_u)
            trial.R = np.random.uniform(r_l, r_u)
            trial.logL = self.log_likelihood(trial)
            self.number += 1

            if (trial.logL > max_likelihood):
                clust.__dict__ = trial.__dict__.copy()
                max_likelihood = trial.logL
                break

            count += 1

        return clust, self.number
Exemple #5
0
    def sample(self):

        """
        Method to pick the sample satisfying the likelihood constraint using metropolis sampling

        Returns
        -------
        metro : object
            The evolved sample
        number : int
            Number of likelihood calculations until now

        """

        metro = Source()
        metro.__dict__ = self.source.__dict__.copy()
        start = Source()
        start.__dict__ = self.source.__dict__.copy()
        new   = Source()
        self.number+=1
        count = 0
        hit = 0
        miss = 0

        x_l, x_u = self.getPrior_X()
        y_l, y_u = self.getPrior_Y()
        r_l, r_u = self.getPrior_R()
        a_l, a_u = self.getPrior_A()

        stepnormalize = self.step/x_u

        stepX    = self.step
        stepY    = stepnormalize*(y_u-y_l)
        stepA    = stepnormalize*(a_u - a_l)
        stepR    = stepnormalize*(r_u-r_l)

        bord = 1

        while(count<20):

            while bord==1:
                bord = 0
                new.X    = metro.X + stepX * (2.*np.random.uniform(0, 1) - 1.);
                new.Y    = metro.Y + stepY * (2.*np.random.uniform(0, 1) - 1.);
                new.A    = metro.A + stepA * (2.*np.random.uniform(0, 1) - 1.);
                new.R    = metro.R + stepR * (2.*np.random.uniform(0, 1) - 1.);



                if(new.X > x_u or new.X < x_l): bord = 1;
                if(new.Y > y_u or new.Y < y_l): bord = 1;
                if(new.A > a_u or new.A < a_l): bord = 1;
                if(new.R > r_u or new.R < r_l): bord = 1;

            new.logL = self.log_likelihood(new)
            self.number+=1

            if(new.logL > self.LC):
                metro.__dict__ = new.__dict__.copy()
                hit+=1
            else:
                miss+=1

            if( hit > miss ):   self.step *= exp(1.0 / hit);
            if( hit < miss ):   self.step /= exp(1.0 / miss);

            stepnormalize = self.step/x_u

            stepX    = self.step
            stepY    = stepnormalize*(y_u-y_l)
            stepA    = stepnormalize*(a_u - a_l)
            stepR    = stepnormalize*(r_u-r_l)


            count+=1
            bord=1

        return metro, self.number
Exemple #6
0
    def sample(self):
        """
        Method to pick the sample satisfying the likelihood constraint using metropolis sampling

        Returns
        -------
        metro : object
            The evolved sample
        number : int
            Number of likelihood calculations until now

        """

        metro = Source()
        metro.__dict__ = self.source.__dict__.copy()
        start = Source()
        start.__dict__ = self.source.__dict__.copy()
        new = Source()
        self.number += 1
        count = 0
        hit = 0
        miss = 0

        x_l, x_u = self.getPrior_X()
        y_l, y_u = self.getPrior_Y()
        r_l, r_u = self.getPrior_R()
        a_l, a_u = self.getPrior_A()

        stepnormalize = self.step / x_u

        stepX = self.step
        stepY = stepnormalize * (y_u - y_l)
        stepA = stepnormalize * (a_u - a_l)
        stepR = stepnormalize * (r_u - r_l)

        bord = 1

        while (count < 20):

            while bord == 1:
                bord = 0
                new.X = metro.X + stepX * (2. * np.random.uniform(0, 1) - 1.)
                new.Y = metro.Y + stepY * (2. * np.random.uniform(0, 1) - 1.)
                new.A = metro.A + stepA * (2. * np.random.uniform(0, 1) - 1.)
                new.R = metro.R + stepR * (2. * np.random.uniform(0, 1) - 1.)

                if (new.X > x_u or new.X < x_l): bord = 1
                if (new.Y > y_u or new.Y < y_l): bord = 1
                if (new.A > a_u or new.A < a_l): bord = 1
                if (new.R > r_u or new.R < r_l): bord = 1

            new.logL = self.log_likelihood(new)
            self.number += 1

            if (new.logL > self.LC):
                metro.__dict__ = new.__dict__.copy()
                hit += 1
            else:
                miss += 1

            if (hit > miss): self.step *= exp(1.0 / hit)
            if (hit < miss): self.step /= exp(1.0 / miss)

            stepnormalize = self.step / x_u

            stepX = self.step
            stepY = stepnormalize * (y_u - y_l)
            stepA = stepnormalize * (a_u - a_l)
            stepR = stepnormalize * (r_u - r_l)

            count += 1
            bord = 1

        return metro, self.number