Exemplo n.º 1
0
    def c_code(self, node, name, ins, outs, sub):
        # support old pickled graphs
        if len(ins) == 2:
            (pvals, unis) = ins
            n = 1
        else:
            (pvals, unis, n) = ins
        (z,) = outs
        if self.odtype == "auto":
            t = f"PyArray_TYPE({pvals})"
        else:
            t = Scalar(self.odtype).dtype_specs()[1]
            if t.startswith("theano_complex"):
                t = t.replace("theano_complex", "NPY_COMPLEX")
            else:
                t = t.upper()
        fail = sub["fail"]
        return (
            """
        if (PyArray_NDIM(%(pvals)s) != 2)
        {
            PyErr_Format(PyExc_TypeError, "pvals ndim should be 2");
            %(fail)s;
        }
        if (PyArray_NDIM(%(unis)s) != 1)
        {
            PyErr_Format(PyExc_TypeError, "unis ndim should be 2");
            %(fail)s;
        }

        if (PyArray_DIMS(%(unis)s)[0] != (PyArray_DIMS(%(pvals)s)[0] * %(n)s))
        {
            PyErr_Format(PyExc_ValueError, "unis.shape[0] != pvals.shape[0] * n");
            %(fail)s;
        }

        if ((NULL == %(z)s)
            || ((PyArray_DIMS(%(z)s))[0] != (PyArray_DIMS(%(pvals)s))[0])
            || ((PyArray_DIMS(%(z)s))[1] != (PyArray_DIMS(%(pvals)s))[1])
        )
        {
            Py_XDECREF(%(z)s);
            %(z)s = (PyArrayObject*) PyArray_EMPTY(2,
                PyArray_DIMS(%(pvals)s),
                %(t)s,
                0);
            if (!%(z)s)
            {
                PyErr_SetString(PyExc_MemoryError, "failed to alloc z output");
                %(fail)s;
            }
        }

        { // NESTED SCOPE

        const int nb_multi = PyArray_DIMS(%(pvals)s)[0];
        const int nb_outcomes = PyArray_DIMS(%(pvals)s)[1];
        const int n_samples = %(n)s;

        //
        // For each multinomial, loop over each possible outcome
        //
        for (int c = 0; c < n_samples; ++c){
            for (int n = 0; n < nb_multi; ++n)
            {
                int waiting = 1;
                double cummul = 0.;
                const dtype_%(unis)s* unis_n = (dtype_%(unis)s*)PyArray_GETPTR1(%(unis)s, c*nb_multi + n);
                for (int m = 0; m < nb_outcomes; ++m)
                {
                    dtype_%(z)s* z_nm = (dtype_%(z)s*)PyArray_GETPTR2(%(z)s, n,m);
                    const dtype_%(pvals)s* pvals_nm = (dtype_%(pvals)s*)PyArray_GETPTR2(%(pvals)s, n,m);
                    cummul += *pvals_nm;
                    if (c == 0)
                    {
                        if (waiting && (cummul > *unis_n))
                        {
                            *z_nm = 1.;
                            waiting = 0;
                        }
                        else
                        {
                            // if we re-used old z pointer, we have to clear it out.
                            *z_nm = 0.;
                        }
                    }
                    else {
                        if (cummul > *unis_n)
                        {
                            *z_nm = *z_nm + 1.;
                            break;
                        }
                    }
                }
            }
        }
        } // END NESTED SCOPE
        """
            % locals()
        )
Exemplo n.º 2
0
    def c_code(self, node, name, ins, outs, sub):
        (pvals, unis, n) = ins
        (z,) = outs
        replace = int(self.replace)
        if self.odtype == "auto":
            t = "NPY_INT64"
        else:
            t = Scalar(self.odtype).dtype_specs()[1]
            if t.startswith("theano_complex"):
                t = t.replace("theano_complex", "NPY_COMPLEX")
            else:
                t = t.upper()
        fail = sub["fail"]
        return (
            """
        // create a copy of pvals matrix
        PyArrayObject* pvals_copy = NULL;

        if (PyArray_NDIM(%(pvals)s) != 2)
        {
            PyErr_Format(PyExc_TypeError, "pvals ndim should be 2");
            %(fail)s;
        }
        if (PyArray_NDIM(%(unis)s) != 1)
        {
            PyErr_Format(PyExc_TypeError, "unis ndim should be 2");
            %(fail)s;
        }

        if ( %(n)s > (PyArray_DIMS(%(pvals)s)[1]) )
        {
            PyErr_Format(PyExc_ValueError, "Cannot sample without replacement n samples bigger than the size of the distribution.");
            %(fail)s;
        }

        if (PyArray_DIMS(%(unis)s)[0] != (PyArray_DIMS(%(pvals)s)[0] * %(n)s))
        {
            PyErr_Format(PyExc_ValueError, "unis.shape[0] != pvals.shape[0] * n");
            %(fail)s;
        }

        pvals_copy = (PyArrayObject*) PyArray_EMPTY(2,
            PyArray_DIMS(%(pvals)s),
            PyArray_TYPE(%(pvals)s),
            0);

        if (!pvals_copy)
        {
            PyErr_SetString(PyExc_MemoryError, "failed to alloc pvals_copy");
            %(fail)s;
        }
        PyArray_CopyInto(pvals_copy, %(pvals)s);

        if ((NULL == %(z)s)
            || ((PyArray_DIMS(%(z)s))[0] != (PyArray_DIMS(%(pvals)s))[0])
            || ((PyArray_DIMS(%(z)s))[1] != %(n)s)
        )
        {
            Py_XDECREF(%(z)s);
            npy_intp dims[2];
            dims[0] = PyArray_DIMS(%(pvals)s)[0];
            dims[1] = %(n)s;
            %(z)s = (PyArrayObject*) PyArray_EMPTY(2,
                dims,
                %(t)s,
                -1);
            if (!%(z)s)
            {
                PyErr_SetString(PyExc_MemoryError, "failed to alloc z output");
                %(fail)s;
            }
        }

        { // NESTED SCOPE

        const int nb_multi = PyArray_DIMS(%(pvals)s)[0];
        const int nb_outcomes = PyArray_DIMS(%(pvals)s)[1];
        const int n_samples = %(n)s;

        //
        // For each multinomial, loop over each possible outcome,
        // and set selected pval to 0 after being selected
        //
        for (int c = 0; c < n_samples; ++c){
            for (int n = 0; n < nb_multi; ++n)
            {
                double cummul = 0.;
                const dtype_%(unis)s* unis_n = (dtype_%(unis)s*)PyArray_GETPTR1(%(unis)s, c*nb_multi + n);
                dtype_%(z)s* z_nc = (dtype_%(z)s*)PyArray_GETPTR2(%(z)s, n, c);
                for (int m = 0; m < nb_outcomes; ++m)
                {
                    dtype_%(pvals)s* pvals_nm = (dtype_%(pvals)s*)PyArray_GETPTR2(pvals_copy, n, m);
                    cummul += *pvals_nm;
                    if (cummul > *unis_n)
                    {
                        *z_nc = m;
                        // No need to renormalize after the last samples.
                        if (c == (n_samples - 1))
                            break;
                        if (! %(replace)s )
                        {
                            // renormalize the nth row of pvals, reuse (cummul-*pvals_nm) to initialize the sum
                            dtype_%(pvals)s sum = cummul - *pvals_nm;
                            dtype_%(pvals)s* pvals_n = (dtype_%(pvals)s*)PyArray_GETPTR2(pvals_copy, n, m);
                            *pvals_nm = 0.;
                            for (int k = m; k < nb_outcomes; ++k)
                            {
                                sum = sum + *pvals_n;
                                pvals_n++;
                            }
                            pvals_n = (dtype_%(pvals)s*)PyArray_GETPTR2(pvals_copy, n, 0);
                            for (int k = 0; k < nb_outcomes; ++k)
                            {
                                *pvals_n = *pvals_n / sum;
                                pvals_n++;
                            }
                        }
                        break;
                    }
                }
            }
        }

        // delete pvals_copy
        {
            Py_XDECREF(pvals_copy);
        }
        } // END NESTED SCOPE
        """
            % locals()
        )