Exemple #1
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    def get_data_from_line(self, batch_left):
        utt_id = self.utt_ids[self.align_ind]
        align = self.alignments[self.align_ind]
        ll = self.likelihoods[utt_id]

        # + 1 since add </s>, need this to match the batches from CharStream
        N = min(len(align) + 1, batch_left)
        data = empty((self.feat_dim, N))
        for k in xrange(0, N):
            if len(align) > 0:
                a = align[max(self.char_ind - 1, 0)]
                llk = ll[:, a:a + SOURCE_CONTEXT]
            else:
                llk = blank_loglikes(1)

            if llk.shape[1] < SOURCE_CONTEXT:
                #llk = gnp.concatenate((llk, uniform_loglikes(SOURCE_CONTEXT - llk.shape[1])), axis=1)
                #llk = np.hstack((llk, uniform_loglikes(SOURCE_CONTEXT - llk.shape[1])))
                llk = np.hstack(
                    (llk, blank_loglikes(SOURCE_CONTEXT - llk.shape[1])))

            data[:, k] = llk.ravel()
            self.char_ind += 1

        return data
Exemple #2
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    def bprop(self):
        logger.debug("%s backprop" % str(self))
        # FIXME Assuming just 1 successor for now
        assert len(self.succ) == 1
        succ_grad = self.succ[0].full_grad

        # FIXME Hack to avoid large sparse matrix multiply
        if type(self.succ[0]) is SumNode:  # Which leads to softmax...
            if self.full_grad is None:
                self.full_grad = empty((self.W.shape[1], succ_grad.shape[1]))
                self.W.grad = empty(self.W.shape)

            for k in range(self.full_grad.shape[0]):
                # TODO self.full_grad[k, :] = ?
                # TODO self.W.grad[k, :] = ?
                pass
        else:
            self.full_grad = mult(self.W.out.T, succ_grad)
            # FIXME Multiplication below is wrong
            self.W.grad = mult(succ_grad, self.succ[0].out.T)

        # TODO Check this
        self.b.grad = succ_grad
Exemple #3
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    def bprop(self):
        logger.debug('%s backprop' % str(self))
        # FIXME Assuming just 1 successor for now
        assert len(self.succ) == 1
        succ_grad = self.succ[0].full_grad

        # FIXME Hack to avoid large sparse matrix multiply
        if type(self.succ[0]) is SumNode:  # Which leads to softmax...
            if self.full_grad is None:
                self.full_grad = empty((self.W.shape[1], succ_grad.shape[1]))
                self.W.grad = empty(self.W.shape)

            for k in range(self.full_grad.shape[0]):
                # TODO self.full_grad[k, :] = ?
                # TODO self.W.grad[k, :] = ?
                pass
        else:
            self.full_grad = mult(self.W.out.T, succ_grad)
            # FIXME Multiplication below is wrong
            self.W.grad = mult(succ_grad, self.succ[0].out.T)

        # TODO Check this
        self.b.grad = succ_grad
Exemple #4
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    def alloc_params(self):
        hps = self.hps

        self.params['Wih'] = vp_init((hps.hidden_size, hps.input_size))
        self.params['Wsh'] = vp_init((hps.hidden_size, hps.source_size))
        self.params['bih'] = zeros((hps.hidden_size, 1))

        for k in xrange(hps.hidden_layers - 1):
            self.params['W%d' % (k+1)] = vp_init((hps.hidden_size, hps.hidden_size))
            self.params['b%d' % (k+1)] = zeros((hps.hidden_size, 1))

        self.params['Who'] = vp_init((hps.output_size, hps.hidden_size))
        self.params['bho'] = zeros((hps.output_size, 1))

        self.count_params()

        # Allocate grads as well

        self.grads = {}
        for k in self.params:
            self.grads[k] = empty(self.params[k].shape)
        logger.info('Allocated gradients')
Exemple #5
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    def get_data_from_line(self, batch_left):
        utt_id = self.utt_ids[self.align_ind]
        align = self.alignments[self.align_ind]
        ll = self.likelihoods[utt_id]

        # + 1 since add </s>, need this to match the batches from CharStream
        N = min(len(align) + 1, batch_left)
        data = empty((self.feat_dim, N))
        for k in xrange(0, N):
            if len(align) > 0:
                a = align[max(self.char_ind-1, 0)]
                llk = ll[:, a:a+SOURCE_CONTEXT]
            else:
                llk = blank_loglikes(1)

            if llk.shape[1] < SOURCE_CONTEXT:
                #llk = gnp.concatenate((llk, uniform_loglikes(SOURCE_CONTEXT - llk.shape[1])), axis=1)
                #llk = np.hstack((llk, uniform_loglikes(SOURCE_CONTEXT - llk.shape[1])))
                llk = np.hstack((llk, blank_loglikes(SOURCE_CONTEXT - llk.shape[1])))

            data[:, k] = llk.ravel()
            self.char_ind += 1

        return data
Exemple #6
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 def __init__(self, name, data_inp, shape, init_fn=None):
     super(IndexedParamNode, self).__init__(name, shape, init_fn=init_fn)
     self.data_inp = data_inp
     self.params_batch = empty(
         (data_inp.feat_dim * self.params.shape[0], data_inp.batch_size))
Exemple #7
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    def cost_and_grad(self, data, labels, back=True, prev_h0=None):
        hps = self.hps
        T = data.shape[1]
        bsize = data.shape[2]

        # FIXME gnumpy reallocates if try and use same parameters?
        #us = self.us[:, 0:T, 0:bsize]
        #dus = self.dus[:, 0:T, 0:bsize]
        #hs = self.hs[:, 0:T, 0:bsize]
        #dhs = self.dhs[:, 0:T, 0:bsize]
        #probs = self.probs[:, 0:T, 0:bsize]
        #dprobs = self.dprobs[:, 0:T, 0:bsize]
        #costs = self.costs[0:T, 0:bsize]

        us = list()
        dus = list()
        hs = list()
        dhs = list()
        h0 = list()
        for k in xrange(hps.hidden_layers):
            us.append(list())
            dus.append(list())
            hs.append(list())
            dhs.append(list())
            h0.append(empty((hps.hidden_size, bsize)))
            for t in xrange(T):
                us[k].append(zeros((hps.hidden_size, bsize)))
                dus[k].append(zeros((hps.hidden_size, bsize)))
                hs[k].append(zeros((hps.hidden_size, bsize)))
                dhs[k].append(zeros((hps.hidden_size, bsize)))
        probs = list()
        for t in xrange(T):
            probs.append(zeros((hps.output_size, bsize)))
        costs = np.zeros((T, bsize))
        if prev_h0 is not None:
            h0 = prev_h0
        else:
            for k in xrange(hps.hidden_layers):
                h0[k] = tile(self.params['h0'][:, k].reshape(-1, 1), bsize)
        bih = self.params['bih']
        Wih = self.params['Wih']
        Whh = self.params['Whh']
        bhh = self.params['bhh']
        Who = self.params['Who']
        bho = self.params['bho']

        # Forward prop

        for t in xrange(T):
            for k in xrange(hps.hidden_layers):
                if t == 0:
                    hprev = h0[k]
                else:
                    hprev = hs[k][t-1]

                if k == 0:
                    us[k][t] = mult(Wih, data[:, t, :]) + bih
                else:
                    us[k][t] = mult(self.params['Wh%d' % k], hs[k-1][t])

                if k == hps.recurrent_layer - 1:
                    us[k][t] += mult(Whh, hprev) + bhh
                    # Clip maximum activation
                    mask = us[k][t] < hps.max_act
                    us[k][t] = us[k][t] * mask + hps.max_act * (1 - mask)
                elif k != 0:
                    us[k][t] += self.params['bh%d' % k]

                hs[k][t] = self.nl(us[k][t])

            probs[t] = softmax(mult(Who, hs[-1][t]) + bho)

        self.last_h = list()
        for k in xrange(hps.hidden_layers):
            self.last_h.append(hs[k][-1])

        if labels is None:
            return None, probs

        probs_neg_log = list()
        dprobs = list()
        for t in xrange(T):
            probs_neg_log.append(as_np(-1 * log(probs[t])))
            dprobs.append(as_np(probs[t].copy()))
        for k in xrange(bsize):
            for t in xrange(len(labels[k])):
                costs[t, k] = probs_neg_log[t][labels[k][t], k]
                dprobs[t][labels[k][t], k] -= 1
        for t in xrange(T):
            dprobs[t] = array(dprobs[t])

        # NOTE Summing costs over time
        # NOTE FIXME Dividing by T to get better sense if objective
        # is decreasing, remove for grad checking
        cost = costs.sum() / bsize / float(T)
        if not back:
            return cost, probs

        # Backprop

        for k in self.grads:
            self.grads[k][:] = 0

        for t in reversed(xrange(T)):
            self.grads['bho'] += dprobs[t][:, :].sum(axis=-1).reshape((-1, 1)) / bsize
            self.grads['Who'] += mult(dprobs[t], hs[-1][t].T) / bsize

            for k in reversed(xrange(hps.hidden_layers)):
                if k == hps.hidden_layers - 1:
                    dhs[k][t] += mult(Who.T, dprobs[t])
                else:
                    dhs[k][t] += mult(self.params['Wh%d' % (k+1)].T, dhs[k+1][t])
                dus[k][t] += get_nl_grad(self.hps.nl, us[k][t]) * dhs[k][t]

                if k > 0:
                    self.grads['Wh%d' % k] += mult(dus[k][t], hs[k-1][t].T) / bsize
                    self.grads['bh%d' % k] += dus[k][t].sum(axis=-1).reshape((-1, 1)) / bsize

                if k == hps.recurrent_layer - 1:
                    if t == 0:
                        hprev = h0[k]
                        self.grads['h0'][:, k] = mult(Whh.T, dus[k][t]).sum(axis=-1) / bsize
                    else:
                        hprev = hs[k][t-1]
                        dhs[k][t-1] = mult(Whh.T, dus[k][t])
                    self.grads['Whh'] += mult(dus[k][t], hprev.T) / bsize
                    self.grads['bhh'] += dus[k][t].sum(axis=-1).reshape((-1, 1)) / bsize

            self.grads['Wih'] += mult(dus[0][t], data[:, t, :].T) / bsize
            self.grads['bih'] += dus[0][t].sum(axis=-1).reshape((-1, 1)) / bsize

        return cost, self.grads
Exemple #8
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    def cost_and_grad(self, data, labels, back=True, prev_h0=None):
        hps = self.hps
        T = data.shape[1]
        bsize = data.shape[2]

        # FIXME gnumpy reallocates if try and use same parameters?
        #us = self.us[:, 0:T, 0:bsize]
        #dus = self.dus[:, 0:T, 0:bsize]
        #hs = self.hs[:, 0:T, 0:bsize]
        #dhs = self.dhs[:, 0:T, 0:bsize]
        #probs = self.probs[:, 0:T, 0:bsize]
        #dprobs = self.dprobs[:, 0:T, 0:bsize]
        #costs = self.costs[0:T, 0:bsize]

        us = list()
        dus = list()
        hs = list()
        dhs = list()
        h0 = list()
        for k in xrange(hps.hidden_layers):
            us.append(list())
            dus.append(list())
            hs.append(list())
            dhs.append(list())
            h0.append(empty((hps.hidden_size, bsize)))
            for t in xrange(T):
                us[k].append(zeros((hps.hidden_size, bsize)))
                dus[k].append(zeros((hps.hidden_size, bsize)))
                hs[k].append(zeros((hps.hidden_size, bsize)))
                dhs[k].append(zeros((hps.hidden_size, bsize)))
        probs = list()
        for t in xrange(T):
            probs.append(zeros((hps.output_size, bsize)))
        costs = np.zeros((T, bsize))
        if prev_h0 is not None:
            h0 = prev_h0
        else:
            for k in xrange(hps.hidden_layers):
                h0[k] = tile(self.params['h0'][:, k].reshape(-1, 1), bsize)
        bih = self.params['bih']
        Wih = self.params['Wih']
        Whh = self.params['Whh']
        bhh = self.params['bhh']
        Who = self.params['Who']
        bho = self.params['bho']

        # Forward prop

        for t in xrange(T):
            for k in xrange(hps.hidden_layers):
                if t == 0:
                    hprev = h0[k]
                else:
                    hprev = hs[k][t - 1]

                if k == 0:
                    us[k][t] = mult(Wih, data[:, t, :]) + bih
                else:
                    us[k][t] = mult(self.params['Wh%d' % k], hs[k - 1][t])

                if k == hps.recurrent_layer - 1:
                    us[k][t] += mult(Whh, hprev) + bhh
                    # Clip maximum activation
                    mask = us[k][t] < hps.max_act
                    us[k][t] = us[k][t] * mask + hps.max_act * (1 - mask)
                elif k != 0:
                    us[k][t] += self.params['bh%d' % k]

                hs[k][t] = self.nl(us[k][t])

            probs[t] = softmax(mult(Who, hs[-1][t]) + bho)

        self.last_h = list()
        for k in xrange(hps.hidden_layers):
            self.last_h.append(hs[k][-1])

        if labels is None:
            return None, probs

        probs_neg_log = list()
        dprobs = list()
        for t in xrange(T):
            probs_neg_log.append(as_np(-1 * log(probs[t])))
            dprobs.append(as_np(probs[t].copy()))
        for k in xrange(bsize):
            for t in xrange(len(labels[k])):
                costs[t, k] = probs_neg_log[t][labels[k][t], k]
                dprobs[t][labels[k][t], k] -= 1
        for t in xrange(T):
            dprobs[t] = array(dprobs[t])

        # NOTE Summing costs over time
        # NOTE FIXME Dividing by T to get better sense if objective
        # is decreasing, remove for grad checking
        cost = costs.sum() / bsize / float(T)
        if not back:
            return cost, probs

        # Backprop

        for k in self.grads:
            self.grads[k][:] = 0

        for t in reversed(xrange(T)):
            self.grads['bho'] += dprobs[t][:, :].sum(axis=-1).reshape(
                (-1, 1)) / bsize
            self.grads['Who'] += mult(dprobs[t], hs[-1][t].T) / bsize

            for k in reversed(xrange(hps.hidden_layers)):
                if k == hps.hidden_layers - 1:
                    dhs[k][t] += mult(Who.T, dprobs[t])
                else:
                    dhs[k][t] += mult(self.params['Wh%d' % (k + 1)].T,
                                      dhs[k + 1][t])
                dus[k][t] += get_nl_grad(self.hps.nl, us[k][t]) * dhs[k][t]

                if k > 0:
                    self.grads['Wh%d' %
                               k] += mult(dus[k][t], hs[k - 1][t].T) / bsize
                    self.grads['bh%d' % k] += dus[k][t].sum(axis=-1).reshape(
                        (-1, 1)) / bsize

                if k == hps.recurrent_layer - 1:
                    if t == 0:
                        hprev = h0[k]
                        self.grads['h0'][:, k] = mult(
                            Whh.T, dus[k][t]).sum(axis=-1) / bsize
                    else:
                        hprev = hs[k][t - 1]
                        dhs[k][t - 1] = mult(Whh.T, dus[k][t])
                    self.grads['Whh'] += mult(dus[k][t], hprev.T) / bsize
                    self.grads['bhh'] += dus[k][t].sum(axis=-1).reshape(
                        (-1, 1)) / bsize

            self.grads['Wih'] += mult(dus[0][t], data[:, t, :].T) / bsize
            self.grads['bih'] += dus[0][t].sum(axis=-1).reshape(
                (-1, 1)) / bsize

        return cost, self.grads
Exemple #9
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 def __init__(self, name, data_inp, shape, init_fn=None):
     super(IndexedParamNode, self).__init__(name, shape, init_fn=init_fn)
     self.data_inp = data_inp
     self.params_batch = empty((data_inp.feat_dim * self.params.shape[0], data_inp.batch_size))
Exemple #10
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 def alloc_grads(self):
     # Call after allocating parameters
     self.grads = {}
     for k in self.params:
         self.grads[k] = empty(self.params[k].shape)
     logger.info('Allocated gradients')
Exemple #11
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 def alloc_grads(self):
     # Call after allocating parameters
     self.grads = {}
     for k in self.params:
         self.grads[k] = empty(self.params[k].shape)
     logger.info('Allocated gradients')