Example #1
0
def check_scalar_grads(precision, backend):
    cgt.reset_config()
    np.random.seed(0)
    cgt.set_precision(precision)
    cgt.core.update_config(backend=backend)
    x = cgt.scalar('x')
    y = cgt.scalar('y')
    z = cgt.scalar('z')
    vars = [x,y,z] #pylint: disable=W0622
    vals = nr.rand(len(vars))+1

    PROB2RESULT = {}

    for ((key,_), cls) in it.chain(
            it.izip(core.UNARY_INFO.items(),it.repeat(core.ElwiseUnary)),
            it.izip(core.BINARY_INFO.items(),it.repeat(core.ElwiseBinary))
            ):
        if key == "conj":
            print "skipping conj"
            continue
        utils.colorprint(utils.Color.YELLOW, "Testing %s\n"%key)
        if cls == core.ElwiseUnary:
            n_in = 1
            op = cls(key)
        else:
            n_in = 2
            op = cls(key, (True,True))
        inputvars = vars[0:n_in]
        inputvals = vals[0:n_in]
        out = core.Result(op, inputvars)
        f = cgt.function(inputvars, out)
        try:
            grads = cgt.grad(out, inputvars)
        except core.NonDifferentiable:
            print "nondiff"
            continue
        if DISPLAY:
            print "Function:"
            cgt.print_tree(out)
            print "Gradient original:"
            cgt.print_tree(grads)
            print "Gradient simplified:"
        grads_simple = core.simplify(grads)
        if DISPLAY: cgt.print_tree(grads_simple)
        gradf = cgt.function(inputvars, grads)
        eps = {"single":1e-4,"double":1e-9}[precision]
        nugrad = numeric_grad(lambda li: f(*li), inputvals,eps=eps) #pylint: disable=W0640
        cgtgrad = gradf(*inputvals)
        np.testing.assert_almost_equal(nugrad,cgtgrad,decimal={"single":3,"double":6}[precision])

        grad_count = core.count_nodes(grads_simple)
        PROB2RESULT[key] = {}
        PROB2RESULT[key]["grad"] = grad_count

    if DISPLAY:
        from thirdparty.tabulate import tabulate
        print tabulate([[key,val["grad"]] for (key,val) in PROB2RESULT.iteritems()],headers=["funcname","gradcount"])    
Example #2
0
def test_scalars():
    np.random.seed(0)
    x = cgt.scalar('x')
    y = cgt.scalar('y')
    z = cgt.scalar('z')
    vars = [x,y,z] #pylint: disable=W0622
    vals = nr.rand(len(vars))+1

    PROB2RESULT = {}

    for ((key,_), cls) in it.chain(
            it.izip(core.UNARY_INFO.items(),it.repeat(core.ElwiseUnary)),
            it.izip(core.BINARY_INFO.items(),it.repeat(core.ElwiseBinary))
            ):
        if key == "conj":
            print "skipping conj"
            continue
        utils.colorprint(utils.Color.YELLOW, "Testing %s\n"%key)
        if cls == core.ElwiseUnary:
            n_in = 1
            op = cls(key)
        else:
            n_in = 2
            op = cls(key, (True,True))
        inputvars = vars[0:n_in]
        inputvals = vals[0:n_in]
        out = core.Result(op, inputvars)
        f = cgt.function(inputvars, out)
        try:
            grads = cgt.grad(out, inputvars)
        except core.NonDifferentiable:
            print "nondiff"
            continue
        if DISPLAY:
            print "Function:"
            cgt.print_tree(out)
            print "Gradient original:"
            cgt.print_tree(grads)
            print "Gradient simplified:"
        grads_simple = core.simplify(grads)
        if DISPLAY: cgt.print_tree(grads_simple)
        gradf = cgt.function(inputvars, grads)
        eps = {"single":1e-4,"double":1e-9}[cgt.get_precision()]
        nugrad = numeric_grad(lambda li: f(*li), inputvals,eps=eps) #pylint: disable=W0640
        cgtgrad = gradf(*inputvals)
        np.testing.assert_almost_equal(nugrad,cgtgrad,decimal={"single":3,"double":6}[cgt.get_precision()])

        grad_count = core.count_nodes(grads_simple)
        PROB2RESULT[key] = {}
        PROB2RESULT[key]["grad"] = grad_count

    if DISPLAY:
        from thirdparty.tabulate import tabulate
        print tabulate([[key,val["grad"]] for (key,val) in PROB2RESULT.iteritems()],headers=["funcname","gradcount"])    
    def __init__(self, n_actions):
        Serializable.__init__(self, n_actions)
        cgt.set_precision('double')
        n_in = 128
        o_no = cgt.matrix("o_no",fixed_shape=(None,n_in))
        a_n = cgt.vector("a_n",dtype='i8')
        q_n = cgt.vector("q_n")
        oldpdist_np = cgt.matrix("oldpdists")

        h0 = (o_no - 128.0)/128.0 
        nhid = 64
        h1 = cgt.tanh(nn.Affine(128,nhid,weight_init=nn.IIDGaussian(std=.1))(h0))
        probs_na = nn.softmax(nn.Affine(nhid,n_actions,weight_init=nn.IIDGaussian(std=0.01))(h1))
        logprobs_na = cgt.log(probs_na)
        b = cgt.size(o_no, 0)
        logps_n = logprobs_na[cgt.arange(b), a_n]
        surr = (logps_n*q_n).mean()
        kl = (oldpdist_np * cgt.log(oldpdist_np/probs_na)).sum(axis=1).mean()

        params = nn.get_parameters(surr)
        gradsurr = cgt.grad(surr, params)
        flatgrad = cgt.concatenate([p.flatten() for p in gradsurr])

        lam = cgt.scalar()
        penobj = surr - lam * kl
        self._f_grad_lagrangian = cgt.function([lam, oldpdist_np, o_no, a_n, q_n], 
            cgt.concatenate([p.flatten() for p in cgt.grad(penobj,params)]))
        self.f_pdist = cgt.function([o_no], probs_na)

        self.f_probs = cgt.function([o_no], probs_na)
        self.f_surr_kl = cgt.function([oldpdist_np, o_no, a_n, q_n], [surr, kl])
        self.f_gradlogp = cgt.function([oldpdist_np, o_no, a_n, q_n], flatgrad)

        self.pc = ParamCollection(params)
 def make_updater_fc():
     X = cgt.matrix("X", fixed_shape=(None, 28 * 28))
     y = cgt.vector("y", dtype="i8")
     stepsize = cgt.scalar("stepsize")
     loss = build_fc_return_loss(X, y)
     params = nn.get_parameters(loss)
     gparams = cgt.grad(loss, params)
     updates = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
     return cgt.function([X, y, stepsize], loss, updates=updates)
Example #5
0
 def make_updater_fc():
     X = cgt.matrix("X", fixed_shape=(None, 28 * 28))
     y = cgt.vector("y", dtype='i8')
     stepsize = cgt.scalar("stepsize")
     loss = build_fc_return_loss(X, y)
     params = nn.get_parameters(loss)
     gparams = cgt.grad(loss, params)
     updates = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
     return cgt.function([X, y, stepsize], loss, updates=updates)
Example #6
0
def test_stack():
    x = cgt.scalar()
    y = cgt.scalar()
    z = cgt.scalar()
    s0 = cgt.stack([x, y, z], axis=0)
    assert cgt.numeric_eval(s0, {x: 1, y: 2, z: 3}).shape == (3, )

    x = cgt.vector()
    y = cgt.vector()
    z = cgt.vector()
    v0 = cgt.stack([x, y, z], axis=0)
    assert cgt.numeric_eval(v0, {
        x: np.zeros(2),
        y: np.zeros(2),
        z: np.zeros(2)
    }).shape == (3, 2)
    v1 = cgt.stack([x, y, z], axis=1)
    assert cgt.numeric_eval(v1, {
        x: np.zeros(2),
        y: np.ones(2),
        z: np.zeros(2)
    }).shape == (2, 3)

    x = cgt.matrix()
    y = cgt.matrix()
    z = cgt.matrix()
    m0 = cgt.stack([x, y, z], axis=0)
    assert cgt.numeric_eval(m0, {
        x: np.zeros((2, 4)),
        y: np.zeros((2, 4)),
        z: np.zeros((2, 4))
    }).shape == (3, 2, 4)
    m1 = cgt.stack([x, y, z], axis=1)
    assert cgt.numeric_eval(m1, {
        x: np.zeros((2, 4)),
        y: np.zeros((2, 4)),
        z: np.zeros((2, 4))
    }).shape == (2, 3, 4)
    m2 = cgt.stack([x, y, z], axis=2)
    assert cgt.numeric_eval(m2, {
        x: np.zeros((2, 4)),
        y: np.zeros((2, 4)),
        z: np.zeros((2, 4))
    }).shape == (2, 4, 3)
Example #7
0
def test_multi_output():
    for x in (cgt.scalar('x'), cgt.vector('x'), cgt.matrix('x')):
        for cls in (SinCos, SinCos2):
            y,z = core.unpack(core.Result(cls(), [x]))
            xnum = np.ones((3,)*x.ndim, cgt.floatX)
            correct = (np.sin(xnum),np.cos(xnum))
            yznum = cgt.numeric_eval([y,z], {x:xnum})
            np.testing.assert_allclose(yznum, correct)
            f = cgt.function([x],[y,z])
            np.testing.assert_allclose(f(xnum), correct)
Example #8
0
def test_incsubtensor1():
    W = cgt.shared(np.zeros((5, 3)), name="W")
    inc = cgt.matrix()  # we'll increment W by this matrix
    incval = np.arange(9).reshape(3, 3)

    start = cgt.scalar(dtype='i8')
    stop = cgt.scalar(dtype='i8')
    updates = {W: cgt.inc_subtensor(W, slice(start, stop), inc)}
    f = cgt.function([start, stop, inc], [], updates=updates)
    f(0, 3, incval)
    assert np.allclose(
        W.op.get_value(),
        np.array([
            [0., 1., 2.],
            [3., 4., 5.],
            [6., 7., 8.],
            [0., 0., 0.],
            [0., 0., 0.],
        ]))
    def make_updater_convnet():
        X = cgt.tensor4("X", fixed_shape=(None, 1, 28, 28))  # so shapes can be inferred
        y = cgt.vector("y", dtype="i8")
        stepsize = cgt.scalar("stepsize")
        loss = build_convnet_return_loss(X, y)

        params = nn.get_parameters(loss)
        gparams = cgt.grad(loss, params)
        updates = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
        return cgt.function([X, y, stepsize], loss, updates=updates)
Example #10
0
def test_incsubtensor1():
    W = cgt.shared(np.zeros((5,3)), name="W")
    inc = cgt.matrix() # we'll increment W by this matrix
    incval = np.arange(9).reshape(3,3)

    start = cgt.scalar(dtype='i8')
    stop = cgt.scalar(dtype='i8')
    updates = {W : cgt.inc_subtensor(W, slice(start, stop), inc)}
    f = cgt.function([start,stop,inc],[],updates=updates)
    f(0,3,incval)
    assert np.allclose(W.op.get_value(), 
        np.array(
        [
         [ 0.,  1.,  2.],
         [ 3.,  4.,  5.],
         [ 6.,  7.,  8.],
         [ 0.,  0.,  0.],
         [ 0.,  0.,  0.],
         ]))
Example #11
0
def test_multi_output():
    for x in (cgt.scalar('x'), cgt.vector('x'), cgt.matrix('x')):
        for cls in (SinCos, SinCos2):
            y, z = core.unpack(core.Result(cls(), [x]))
            xnum = np.ones((3, ) * x.ndim, cgt.floatX)
            correct = (np.sin(xnum), np.cos(xnum))
            yznum = cgt.numeric_eval([y, z], {x: xnum})
            np.testing.assert_allclose(yznum, correct)
            f = cgt.function([x], [y, z])
            np.testing.assert_allclose(f(xnum), correct)
Example #12
0
    def __init__(self, obs_dim, ctrl_dim):

        cgt.set_precision('double')
        Serializable.__init__(self, obs_dim, ctrl_dim)

        self.obs_dim = obs_dim
        self.ctrl_dim = ctrl_dim

        o_no = cgt.matrix("o_no",fixed_shape=(None,obs_dim))
        a_na = cgt.matrix("a_na",fixed_shape = (None, ctrl_dim))
        adv_n = cgt.vector("adv_n")
        oldpdist_np = cgt.matrix("oldpdist", fixed_shape=(None, 2*ctrl_dim))
        self.logstd = logstd_1a = nn.parameter(np.zeros((1, self.ctrl_dim)), name="std_1a")
        std_1a = cgt.exp(logstd_1a)

        # Here's where we apply the network
        h0 = o_no
        nhid = 32
        h1 = cgt.tanh(nn.Affine(obs_dim,nhid,weight_init=nn.IIDGaussian(std=0.1))(h0))
        h2 = cgt.tanh(nn.Affine(nhid,nhid,weight_init=nn.IIDGaussian(std=0.1))(h1))
        mean_na = nn.Affine(nhid,ctrl_dim,weight_init=nn.IIDGaussian(std=0.01))(h2)

        b = cgt.size(o_no, 0)
        std_na = cgt.repeat(std_1a, b, axis=0)

        oldmean_na = oldpdist_np[:, 0:self.ctrl_dim]
        oldstd_na = oldpdist_np[:, self.ctrl_dim:2*self.ctrl_dim]

        logp_n = ((-.5) * cgt.square( (a_na - mean_na) / std_na ).sum(axis=1)) - logstd_1a.sum()
        oldlogp_n = ((-.5) * cgt.square( (a_na - oldmean_na) / oldstd_na ).sum(axis=1)) - cgt.log(oldstd_na).sum(axis=1)

        ratio_n = cgt.exp(logp_n - oldlogp_n)

        surr = (ratio_n*adv_n).mean()

        pdists_np = cgt.concatenate([mean_na, std_na], axis=1)
        # kl = cgt.log(sigafter/)

        params = nn.get_parameters(surr)

        oldvar_na = cgt.square(oldstd_na)
        var_na = cgt.square(std_na)
        kl = (cgt.log(std_na / oldstd_na) + (oldvar_na + cgt.square(oldmean_na - mean_na)) / (2 * var_na) - .5).sum(axis=1).mean()


        lam = cgt.scalar()
        penobj = surr - lam * kl
        self._compute_surr_kl = cgt.function([oldpdist_np, o_no, a_na, adv_n], [surr, kl])
        self._compute_grad_lagrangian = cgt.function([lam, oldpdist_np, o_no, a_na, adv_n], 
            cgt.concatenate([p.flatten() for p in cgt.grad(penobj,params)]))
        self.f_pdist = cgt.function([o_no], pdists_np)

        self.f_objs = cgt.function([oldpdist_np, o_no, a_na, adv_n], [surr, kl])

        self.pc = ParamCollection(params)
Example #13
0
def test_scalar_input():
    x = cgt.scalar()
    f = cgt.function([x], x**2)
    xval = 2
    yval = 4
    assert np.allclose(f(2), 4)
    assert np.allclose(f(2.0), 4)    
    assert np.allclose(f(np.array(2)), 4)      
    assert np.allclose(f(np.array(2.0)), 4)    
    assert np.allclose(f(np.array([2])[0]), 4)        
    assert np.allclose(f(np.array([2.0])[0]), 4)        
Example #14
0
    def make_updater_convnet():
        X = cgt.tensor4("X", fixed_shape=(None, 1, 28,
                                          28))  # so shapes can be inferred
        y = cgt.vector("y", dtype='i8')
        stepsize = cgt.scalar("stepsize")
        loss = build_convnet_return_loss(X, y)

        params = nn.get_parameters(loss)
        gparams = cgt.grad(loss, params)
        updates = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
        return cgt.function([X, y, stepsize], loss, updates=updates)
Example #15
0
def test_sleeps():
    with cgt.scoped_update_config(parallel=True):
        x = cgt.scalar('x')
        y1 = sleepfor(x, .1)
        y2 = sleepfor(x, .1)

        z = y1 + y2
        fpar = cgt.function([x], z)

        tstart = time.time()
        fpar(0)
        elapsed = time.time() - tstart
        assert elapsed < .11
Example #16
0
def test_sleeps():
    with cgt.scoped_update_config(parallel = True, backend="native"):
        x = cgt.scalar('x')
        y1 = sleepfor(x, .1)
        y2 = sleepfor(x, .1)

        z=y1+y2
        fpar = cgt.function([x],z)
        
        tstart = time.time()
        fpar(0)
        elapsed = time.time() - tstart
        assert elapsed < .11
Example #17
0
    def runTest(self):
        if cgt.get_config()["backend"] != "python":
            cgt.utils.warn("Skipping test -- only works for backend=python")
            return
        x = cgt.scalar()
        with cgt.debug_context() as dbg:
            cgt.assert_(cgt.equal(x, 1),"yoyoyo")
            cgt.dbg_call(myfunc, x)
            print "dbg",dbg.nodes
            # cgt.assert_(cgt.equal(x, 2))

        f = cgt.make_function([x],[x],dbg=dbg)
        f(1)
        with self.assertRaises(AssertionError):
            f(2)
Example #18
0
    def runTest(self):
        if cgt.get_config()["backend"] != "python":
            cgt.utils.warn("Skipping test -- only works for backend=python")
            return
        x = cgt.scalar()
        with cgt.debug_context() as dbg:
            cgt.assert_(cgt.equal(x, 1), "yoyoyo")
            cgt.dbg_call(myfunc, x)
            print "dbg", dbg.nodes
            # cgt.assert_(cgt.equal(x, 2))

        f = cgt.make_function([x], [x], dbg=dbg)
        f(1)
        with self.assertRaises(AssertionError):
            f(2)
Example #19
0
def test_stack():
    x = cgt.scalar()
    y = cgt.scalar()
    z = cgt.scalar()
    s0 = cgt.stack([x, y, z], axis=0)
    assert cgt.numeric_eval(s0, {x: 1, y: 2, z: 3}).shape == (3,)

    x = cgt.vector()
    y = cgt.vector()
    z = cgt.vector()
    v0 = cgt.stack([x, y, z], axis=0)
    assert cgt.numeric_eval(v0, {x: np.zeros(2), y: np.zeros(2), z: np.zeros(2)}).shape == (3, 2)
    v1 = cgt.stack([x, y, z], axis=1)
    assert cgt.numeric_eval(v1, {x: np.zeros(2), y: np.ones(2), z: np.zeros(2)}).shape == (2, 3)

    x = cgt.matrix()
    y = cgt.matrix()
    z = cgt.matrix()
    m0 = cgt.stack([x, y, z], axis=0)
    assert cgt.numeric_eval(m0, {x: np.zeros((2, 4)), y: np.zeros((2, 4)), z: np.zeros((2, 4))}).shape == (3, 2, 4)
    m1 = cgt.stack([x, y, z], axis=1)
    assert cgt.numeric_eval(m1, {x: np.zeros((2, 4)), y: np.zeros((2, 4)), z: np.zeros((2, 4))}).shape == (2, 3, 4)
    m2 = cgt.stack([x, y, z], axis=2)
    assert cgt.numeric_eval(m2, {x: np.zeros((2, 4)), y: np.zeros((2, 4)), z: np.zeros((2, 4))}).shape == (2, 4, 3)
Example #20
0
    def make_updater_fc_parallel():
        X = cgt.matrix("X", fixed_shape=(None, 28 * 28))
        y = cgt.vector("y", dtype='i8')
        stepsize = cgt.scalar("stepsize")

        loss = build_fc_return_loss(X, y)
        params = nn.get_parameters(loss)
        m = nn.Module([X, y], [loss])
        split_loss = 0
        for start in xrange(0, batch_size, batch_size // 4):
            sli = slice(start, start + batch_size // 4)
            split_loss += m([X[sli], y[sli]])[0]
        split_loss /= 4
        gparams = cgt.grad(split_loss, params)
        updates2 = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
        return cgt.function([X, y, stepsize], split_loss, updates=updates2)
    def make_updater_convnet_parallel():
        X = cgt.tensor4("X", fixed_shape=(None, 1, 28, 28))  # so shapes can be inferred
        y = cgt.vector("y", dtype="i8")
        stepsize = cgt.scalar("stepsize")
        loss = build_convnet_return_loss(X, y)

        m = nn.Module([X, y], [loss])
        split_loss = 0
        for start in xrange(0, batch_size, batch_size // 4):
            sli = slice(start, start + batch_size // 4)
            split_loss += m([X[sli], y[sli]])[0]
        split_loss /= 4
        params = nn.get_parameters(loss)
        gparams = cgt.grad(split_loss, params)
        updates2 = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
        return cgt.function([X, y, stepsize], split_loss, updates=updates2)
    def make_updater_fc_parallel():
        X = cgt.matrix("X", fixed_shape=(None,28*28))
        y = cgt.vector("y",dtype='i8')
        stepsize = cgt.scalar("stepsize")

        loss = build_fc_return_loss(X,y)
        params = nn.get_parameters(loss)        
        m = nn.Module([X,y], [loss])
        split_loss = 0
        for start in xrange(0, batch_size, batch_size//4):
            sli = slice(start, start+batch_size//4)
            split_loss += m([X[sli], y[sli]])[0]
        split_loss /= 4
        gparams = cgt.grad(split_loss, params)
        updates2 = [(p, p-stepsize*gp) for (p, gp) in zip(params, gparams)]
        return cgt.function([X,y, stepsize], split_loss, updates=updates2)
Example #23
0
def test_linreg():
    cgt.reset_config()
    cgt.set_precision('double')
    N = 10
    K = 3

    Xval = np.random.randn(N, K)
    wval = np.random.randn(K)
    bval = np.random.randn()
    yval = np.random.randn(N)

    X_nk = cgt.matrix("X")
    y_n = cgt.vector("y")
    w_k = cgt.vector("w")
    b = cgt.scalar(name="b")

    ypred = cgt.dot(X_nk, w_k) + b

    err = cgt.sum(cgt.square(ypred - y_n))
    g = cgt.grad(err, [w_k, b])

    g_simple, an, _ = cgt.core.simplify_and_analyze(g)

    print "Loss function:"
    cgt.print_tree([err])
    print "Gradient:"
    cgt.print_tree(g)

    print "Gradient simplified"
    cgt.print_tree(
        g_simple,
        nodefn=lambda node, o: o.write(" " + an["node2hash"][node][:5]))

    print "-------"

    d = {X_nk: Xval, w_k: wval, b: bval, y_n: yval}

    np.testing.assert_allclose(cgt.numeric_eval(err, d),
                               np.linalg.norm(Xval.dot(wval) + bval - yval)**2)
    np.testing.assert_allclose(cgt.numeric_eval(g[0], d),
                               2 * Xval.T.dot(Xval.dot(wval) + bval - yval))
    np.testing.assert_allclose(cgt.numeric_eval(g[1], d),
                               2 * np.sum(Xval.dot(wval) + bval - yval, 0))
Example #24
0
 def __init__(self, num_features=None, num_hidden=100):
     stepsize = 0.01
     # with shape (batchsize, ncols)
     X = cgt.matrix("X", fixed_shape=(1, num_features))
     # y: a symbolic variable representing the rewards, which are integers
     y = cgt.scalar("y", dtype='float64')
     
     hid1 = nn.rectify(
         nn.Affine(num_features, num_hidden, weight_init=nn.IIDGaussian(std=.1), bias_init=nn.Constant(1))(X)
     )
     # One final fully-connected layer, and then a linear activation output for reward
     output = nn.Affine(num_hidden, 1, weight_init=nn.IIDGaussian(std=.1), bias_init=nn.Constant(1))(hid1)
     abs_deviation = cgt.abs(output - y).mean()
     params = nn.get_parameters(abs_deviation)
     gparams = cgt.grad(abs_deviation, params)
     
     updates = [(p, p-stepsize*gp) for (p, gp) in zip(params, gparams)]
     self.predictor = cgt.function([X], output)
     self.updater = cgt.function([X, y], abs_deviation, updates=updates)
Example #25
0
def test_linreg():
    N = 10
    K = 3

    Xval = np.random.randn(N,K)
    wval = np.random.randn(K)
    bval = np.random.randn()
    yval = np.random.randn(N)

    X_nk = cgt.matrix("X")
    y_n = cgt.vector("y")
    w_k = cgt.vector("w")
    b = cgt.scalar(name="b")

    ypred = cgt.dot(X_nk, w_k) + b

    err = cgt.sum(cgt.square(ypred - y_n))
    g = cgt.grad(err, [w_k, b])

    g_simple,an,_ = cgt.core.simplify_and_analyze(g)


    print "Loss function:"
    cgt.print_tree([err])
    print "Gradient:"
    cgt.print_tree(g)

    print "Gradient simplified"
    cgt.print_tree(g_simple, nodefn=lambda node,o: o.write(" " + an["node2hash"][node][:5]))

    print "-------"

    d = {X_nk : Xval, w_k : wval, b : bval, y_n : yval}

    np.testing.assert_allclose(cgt.numeric_eval(err,d), np.linalg.norm(Xval.dot(wval) + bval - yval)**2,
        atol={"single":1e-3,"double":1e-6}[cgt.get_precision()])
    np.testing.assert_allclose(cgt.numeric_eval(g[0],d), 2 * Xval.T.dot(Xval.dot(wval) + bval - yval),
        atol={"single":1e-3,"double":1e-6}[cgt.get_precision()])
    np.testing.assert_allclose(cgt.numeric_eval(g[1],d), 2 *  np.sum(Xval.dot(wval) + bval - yval, 0),
        atol={"single":1e-3,"double":1e-6}[cgt.get_precision()])
Example #26
0
    def __init__(self, n_actions):
        Serializable.__init__(self, n_actions)
        cgt.set_precision('double')
        n_in = 128
        o_no = cgt.matrix("o_no", fixed_shape=(None, n_in))
        a_n = cgt.vector("a_n", dtype='i8')
        q_n = cgt.vector("q_n")
        oldpdist_np = cgt.matrix("oldpdists")

        h0 = (o_no - 128.0) / 128.0
        nhid = 64
        h1 = cgt.tanh(
            nn.Affine(128, nhid, weight_init=nn.IIDGaussian(std=.1))(h0))
        probs_na = nn.softmax(
            nn.Affine(nhid, n_actions,
                      weight_init=nn.IIDGaussian(std=0.01))(h1))
        logprobs_na = cgt.log(probs_na)
        b = cgt.size(o_no, 0)
        logps_n = logprobs_na[cgt.arange(b), a_n]
        surr = (logps_n * q_n).mean()
        kl = (oldpdist_np * cgt.log(oldpdist_np / probs_na)).sum(axis=1).mean()

        params = nn.get_parameters(surr)
        gradsurr = cgt.grad(surr, params)
        flatgrad = cgt.concatenate([p.flatten() for p in gradsurr])

        lam = cgt.scalar()
        penobj = surr - lam * kl
        self._f_grad_lagrangian = cgt.function(
            [lam, oldpdist_np, o_no, a_n, q_n],
            cgt.concatenate([p.flatten() for p in cgt.grad(penobj, params)]))
        self.f_pdist = cgt.function([o_no], probs_na)

        self.f_probs = cgt.function([o_no], probs_na)
        self.f_surr_kl = cgt.function([oldpdist_np, o_no, a_n, q_n],
                                      [surr, kl])
        self.f_gradlogp = cgt.function([oldpdist_np, o_no, a_n, q_n], flatgrad)

        self.pc = ParamCollection(params)
Example #27
0
    def __init__(self, num_features=None, num_hidden=100):
        stepsize = 0.01
        # with shape (batchsize, ncols)
        X = cgt.matrix("X", fixed_shape=(1, num_features))
        # y: a symbolic variable representing the rewards, which are integers
        y = cgt.scalar("y", dtype='float64')

        hid1 = nn.rectify(
            nn.Affine(num_features,
                      num_hidden,
                      weight_init=nn.IIDGaussian(std=.1),
                      bias_init=nn.Constant(1))(X))
        # One final fully-connected layer, and then a linear activation output for reward
        output = nn.Affine(num_hidden,
                           1,
                           weight_init=nn.IIDGaussian(std=.1),
                           bias_init=nn.Constant(1))(hid1)
        abs_deviation = cgt.abs(output - y).mean()
        params = nn.get_parameters(abs_deviation)
        gparams = cgt.grad(abs_deviation, params)

        updates = [(p, p - stepsize * gp) for (p, gp) in zip(params, gparams)]
        self.predictor = cgt.function([X], output)
        self.updater = cgt.function([X, y], abs_deviation, updates=updates)
Example #28
0
def scalar(name):
    return cgt.scalar(name)
Example #29
0
from __future__ import print_function
import cgt

a = cgt.scalar('a')
b = cgt.scalar('b')

y = a * b

multiply = cgt.function([a,b], y)

print(multiply(1, 2)) # 2
print(multiply(3, 3)) # 9
Example #30
0
def scalar(name):
    return cgt.scalar(name)
Example #31
0
    def __init__(self, obs_dim, ctrl_dim):

        cgt.set_precision('double')
        Serializable.__init__(self, obs_dim, ctrl_dim)

        self.obs_dim = obs_dim
        self.ctrl_dim = ctrl_dim

        o_no = cgt.matrix("o_no", fixed_shape=(None, obs_dim))
        a_na = cgt.matrix("a_na", fixed_shape=(None, ctrl_dim))
        adv_n = cgt.vector("adv_n")
        oldpdist_np = cgt.matrix("oldpdist", fixed_shape=(None, 2 * ctrl_dim))
        self.logstd = logstd_1a = nn.parameter(np.zeros((1, self.ctrl_dim)),
                                               name="std_1a")
        std_1a = cgt.exp(logstd_1a)

        # Here's where we apply the network
        h0 = o_no
        nhid = 32
        h1 = cgt.tanh(
            nn.Affine(obs_dim, nhid, weight_init=nn.IIDGaussian(std=0.1))(h0))
        h2 = cgt.tanh(
            nn.Affine(nhid, nhid, weight_init=nn.IIDGaussian(std=0.1))(h1))
        mean_na = nn.Affine(nhid,
                            ctrl_dim,
                            weight_init=nn.IIDGaussian(std=0.01))(h2)

        b = cgt.size(o_no, 0)
        std_na = cgt.repeat(std_1a, b, axis=0)

        oldmean_na = oldpdist_np[:, 0:self.ctrl_dim]
        oldstd_na = oldpdist_np[:, self.ctrl_dim:2 * self.ctrl_dim]

        logp_n = ((-.5) * cgt.square(
            (a_na - mean_na) / std_na).sum(axis=1)) - logstd_1a.sum()
        oldlogp_n = ((-.5) * cgt.square(
            (a_na - oldmean_na) / oldstd_na).sum(axis=1)
                     ) - cgt.log(oldstd_na).sum(axis=1)

        ratio_n = cgt.exp(logp_n - oldlogp_n)

        surr = (ratio_n * adv_n).mean()

        pdists_np = cgt.concatenate([mean_na, std_na], axis=1)
        # kl = cgt.log(sigafter/)

        params = nn.get_parameters(surr)

        oldvar_na = cgt.square(oldstd_na)
        var_na = cgt.square(std_na)
        kl = (cgt.log(std_na / oldstd_na) +
              (oldvar_na + cgt.square(oldmean_na - mean_na)) / (2 * var_na) -
              .5).sum(axis=1).mean()

        lam = cgt.scalar()
        penobj = surr - lam * kl
        self._compute_surr_kl = cgt.function([oldpdist_np, o_no, a_na, adv_n],
                                             [surr, kl])
        self._compute_grad_lagrangian = cgt.function(
            [lam, oldpdist_np, o_no, a_na, adv_n],
            cgt.concatenate([p.flatten() for p in cgt.grad(penobj, params)]))
        self.f_pdist = cgt.function([o_no], pdists_np)

        self.f_objs = cgt.function([oldpdist_np, o_no, a_na, adv_n],
                                   [surr, kl])

        self.pc = ParamCollection(params)