diff --git a/acb_poly.h b/acb_poly.h
index b43be299..65a71eed 100644
--- a/acb_poly.h
+++ b/acb_poly.h
@@ -173,6 +173,10 @@ void acb_poly_set(acb_poly_t dest, const acb_poly_t src);
 
 void acb_poly_set_round(acb_poly_t dest, const acb_poly_t src, slong prec);
 
+void acb_poly_set_trunc(acb_poly_t res, const acb_poly_t poly, slong n);
+
+void acb_poly_set_trunc_round(acb_poly_t res, const acb_poly_t poly, slong n, slong prec);
+
 void acb_poly_set_arb_poly(acb_poly_t poly, const arb_poly_t re);
 
 void acb_poly_set2_arb_poly(acb_poly_t poly, const arb_poly_t re, const arb_poly_t im);
diff --git a/acb_poly/set_trunc.c b/acb_poly/set_trunc.c
new file mode 100644
index 00000000..4aa57bd5
--- /dev/null
+++ b/acb_poly/set_trunc.c
@@ -0,0 +1,35 @@
+/*
+    Copyright (C) 2016 Fredrik Johansson
+
+    This file is part of Arb.
+
+    Arb is free software: you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.  See <http://www.gnu.org/licenses/>.
+*/
+
+#include "acb_poly.h"
+
+
+void
+acb_poly_set_trunc(acb_poly_t res, const acb_poly_t poly, slong n)
+{
+    if (poly == res)
+    {
+        acb_poly_truncate(res, n);
+    }
+    else
+    {
+        slong rlen;
+
+        rlen = FLINT_MIN(n, poly->length);
+        while (rlen > 0 && acb_is_zero(poly->coeffs + rlen - 1))
+            rlen--;
+
+        acb_poly_fit_length(res, rlen);
+        _acb_vec_set(res->coeffs, poly->coeffs, rlen);
+        _acb_poly_set_length(res, rlen);
+    }
+}
+
diff --git a/acb_poly/set_trunc_round.c b/acb_poly/set_trunc_round.c
new file mode 100644
index 00000000..4bc41630
--- /dev/null
+++ b/acb_poly/set_trunc_round.c
@@ -0,0 +1,36 @@
+/*
+    Copyright (C) 2016 Fredrik Johansson
+
+    This file is part of Arb.
+
+    Arb is free software: you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.  See <http://www.gnu.org/licenses/>.
+*/
+
+#include "acb_poly.h"
+
+
+void
+acb_poly_set_trunc_round(acb_poly_t res, const acb_poly_t poly, slong n, slong prec)
+{
+    if (poly == res)
+    {
+        acb_poly_truncate(res, n);
+        _acb_vec_set_round(res->coeffs, res->coeffs, res->length, prec);
+    }
+    else
+    {
+        slong rlen;
+
+        rlen = FLINT_MIN(n, poly->length);
+        while (rlen > 0 && acb_is_zero(poly->coeffs + rlen - 1))
+            rlen--;
+
+        acb_poly_fit_length(res, rlen);
+        _acb_vec_set_round(res->coeffs, poly->coeffs, rlen, prec);
+        _acb_poly_set_length(res, rlen);
+    }
+}
+
diff --git a/acb_poly/test/t-set_trunc_round.c b/acb_poly/test/t-set_trunc_round.c
new file mode 100644
index 00000000..b8e29689
--- /dev/null
+++ b/acb_poly/test/t-set_trunc_round.c
@@ -0,0 +1,79 @@
+/*
+    Copyright (C) 2016 Fredrik Johansson
+
+    This file is part of Arb.
+
+    Arb is free software: you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.  See <http://www.gnu.org/licenses/>.
+*/
+
+#include "acb_poly.h"
+
+int
+main(void)
+{
+    int iter;
+    flint_rand_t state;
+
+    flint_printf("set_trunc_round....");
+    fflush(stdout);
+
+    flint_randinit(state);
+
+    for (iter = 0; iter < 1000 * arb_test_multiplier(); iter++)
+    {
+        acb_poly_t a, b, c, d, e;
+        slong n, prec;
+
+        acb_poly_init(a);
+        acb_poly_init(b);
+        acb_poly_init(c);
+        acb_poly_init(d);
+        acb_poly_init(e);
+
+        acb_poly_randtest(a, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        acb_poly_randtest(b, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        acb_poly_randtest(c, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        acb_poly_randtest(d, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        acb_poly_randtest(e, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+
+        n = n_randint(state, 10);
+        prec = 2 + n_randint(state, 200);
+
+        acb_poly_set_trunc(b, a, n);
+        acb_poly_set_round(b, b, prec);
+
+        acb_poly_set_round(c, a, prec);
+        acb_poly_set_trunc(c, c, n);
+
+        acb_poly_set_trunc_round(d, a, n, prec);
+
+        acb_poly_set(e, a);
+        acb_poly_set_trunc_round(e, e, n, prec);
+
+        if (!acb_poly_equal(b, c) || !acb_poly_equal(c, d) || !acb_poly_equal(d, e))
+        {
+            flint_printf("FAIL\n\n");
+            acb_poly_printd(a, 50), flint_printf("\n\n");
+            acb_poly_printd(b, 50), flint_printf("\n\n");
+            acb_poly_printd(c, 50), flint_printf("\n\n");
+            acb_poly_printd(d, 50), flint_printf("\n\n");
+            acb_poly_printd(e, 50), flint_printf("\n\n");
+            abort();
+        }
+
+        acb_poly_clear(a);
+        acb_poly_clear(b);
+        acb_poly_clear(c);
+        acb_poly_clear(d);
+        acb_poly_clear(e);
+    }
+
+    flint_randclear(state);
+    flint_cleanup();
+    flint_printf("PASS\n");
+    return 0;
+}
+
diff --git a/arb_poly.h b/arb_poly.h
index b580c43d..684d0da4 100644
--- a/arb_poly.h
+++ b/arb_poly.h
@@ -65,6 +65,10 @@ void arb_poly_set(arb_poly_t poly, const arb_poly_t src);
 
 void arb_poly_set_round(arb_poly_t poly, const arb_poly_t src, slong prec);
 
+void arb_poly_set_trunc(arb_poly_t res, const arb_poly_t poly, slong n);
+
+void arb_poly_set_trunc_round(arb_poly_t res, const arb_poly_t poly, slong n, slong prec);
+
 /* Basic manipulation */
 
 ARB_POLY_INLINE slong arb_poly_length(const arb_poly_t poly)
diff --git a/arb_poly/set_trunc.c b/arb_poly/set_trunc.c
new file mode 100644
index 00000000..5f1206fe
--- /dev/null
+++ b/arb_poly/set_trunc.c
@@ -0,0 +1,35 @@
+/*
+    Copyright (C) 2016 Fredrik Johansson
+
+    This file is part of Arb.
+
+    Arb is free software: you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.  See <http://www.gnu.org/licenses/>.
+*/
+
+#include "arb_poly.h"
+
+
+void
+arb_poly_set_trunc(arb_poly_t res, const arb_poly_t poly, slong n)
+{
+    if (poly == res)
+    {
+        arb_poly_truncate(res, n);
+    }
+    else
+    {
+        slong rlen;
+
+        rlen = FLINT_MIN(n, poly->length);
+        while (rlen > 0 && arb_is_zero(poly->coeffs + rlen - 1))
+            rlen--;
+
+        arb_poly_fit_length(res, rlen);
+        _arb_vec_set(res->coeffs, poly->coeffs, rlen);
+        _arb_poly_set_length(res, rlen);
+    }
+}
+
diff --git a/arb_poly/set_trunc_round.c b/arb_poly/set_trunc_round.c
new file mode 100644
index 00000000..321c7b4b
--- /dev/null
+++ b/arb_poly/set_trunc_round.c
@@ -0,0 +1,36 @@
+/*
+    Copyright (C) 2016 Fredrik Johansson
+
+    This file is part of Arb.
+
+    Arb is free software: you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.  See <http://www.gnu.org/licenses/>.
+*/
+
+#include "arb_poly.h"
+
+
+void
+arb_poly_set_trunc_round(arb_poly_t res, const arb_poly_t poly, slong n, slong prec)
+{
+    if (poly == res)
+    {
+        arb_poly_truncate(res, n);
+        _arb_vec_set_round(res->coeffs, res->coeffs, res->length, prec);
+    }
+    else
+    {
+        slong rlen;
+
+        rlen = FLINT_MIN(n, poly->length);
+        while (rlen > 0 && arb_is_zero(poly->coeffs + rlen - 1))
+            rlen--;
+
+        arb_poly_fit_length(res, rlen);
+        _arb_vec_set_round(res->coeffs, poly->coeffs, rlen, prec);
+        _arb_poly_set_length(res, rlen);
+    }
+}
+
diff --git a/arb_poly/test/t-set_trunc_round.c b/arb_poly/test/t-set_trunc_round.c
new file mode 100644
index 00000000..3243ee02
--- /dev/null
+++ b/arb_poly/test/t-set_trunc_round.c
@@ -0,0 +1,79 @@
+/*
+    Copyright (C) 2016 Fredrik Johansson
+
+    This file is part of Arb.
+
+    Arb is free software: you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.  See <http://www.gnu.org/licenses/>.
+*/
+
+#include "arb_poly.h"
+
+int
+main(void)
+{
+    int iter;
+    flint_rand_t state;
+
+    flint_printf("set_trunc_round....");
+    fflush(stdout);
+
+    flint_randinit(state);
+
+    for (iter = 0; iter < 1000 * arb_test_multiplier(); iter++)
+    {
+        arb_poly_t a, b, c, d, e;
+        slong n, prec;
+
+        arb_poly_init(a);
+        arb_poly_init(b);
+        arb_poly_init(c);
+        arb_poly_init(d);
+        arb_poly_init(e);
+
+        arb_poly_randtest(a, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        arb_poly_randtest(b, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        arb_poly_randtest(c, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        arb_poly_randtest(d, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+        arb_poly_randtest(e, state, n_randint(state, 10), 2 + n_randint(state, 200), 10);
+
+        n = n_randint(state, 10);
+        prec = 2 + n_randint(state, 200);
+
+        arb_poly_set_trunc(b, a, n);
+        arb_poly_set_round(b, b, prec);
+
+        arb_poly_set_round(c, a, prec);
+        arb_poly_set_trunc(c, c, n);
+
+        arb_poly_set_trunc_round(d, a, n, prec);
+
+        arb_poly_set(e, a);
+        arb_poly_set_trunc_round(e, e, n, prec);
+
+        if (!arb_poly_equal(b, c) || !arb_poly_equal(c, d) || !arb_poly_equal(d, e))
+        {
+            flint_printf("FAIL\n\n");
+            arb_poly_printd(a, 50), flint_printf("\n\n");
+            arb_poly_printd(b, 50), flint_printf("\n\n");
+            arb_poly_printd(c, 50), flint_printf("\n\n");
+            arb_poly_printd(d, 50), flint_printf("\n\n");
+            arb_poly_printd(e, 50), flint_printf("\n\n");
+            abort();
+        }
+
+        arb_poly_clear(a);
+        arb_poly_clear(b);
+        arb_poly_clear(c);
+        arb_poly_clear(d);
+        arb_poly_clear(e);
+    }
+
+    flint_randclear(state);
+    flint_cleanup();
+    flint_printf("PASS\n");
+    return 0;
+}
+
diff --git a/doc/source/acb_poly.rst b/doc/source/acb_poly.rst
index 8dc7b298..868fdbbb 100644
--- a/doc/source/acb_poly.rst
+++ b/doc/source/acb_poly.rst
@@ -101,6 +101,12 @@ Basic properties and manipulation
 
     Sets *dest* to a copy of *src*, rounded to *prec* bits.
 
+.. function:: void acb_poly_set_trunc(acb_poly_t dest, const acb_poly_t src, slong n)
+
+.. function:: void acb_poly_set_trunc_round(acb_poly_t dest, const acb_poly_t src, slong n, slong prec)
+
+    Sets *dest* to a copy of *src*, truncated to length *n* and rounded to *prec* bits.
+
 .. function:: void acb_poly_set_coeff_si(acb_poly_t poly, slong n, slong c)
 
 .. function:: void acb_poly_set_coeff_acb(acb_poly_t poly, slong n, const acb_t c)
diff --git a/doc/source/arb_poly.rst b/doc/source/arb_poly.rst
index 4b107e84..226b0f1a 100644
--- a/doc/source/arb_poly.rst
+++ b/doc/source/arb_poly.rst
@@ -95,6 +95,12 @@ Basic manipulation
 
     Sets *dest* to a copy of *src*, rounded to *prec* bits.
 
+.. function:: void arb_poly_set_trunc(arb_poly_t dest, const arb_poly_t src, slong n)
+
+.. function:: void arb_poly_set_trunc_round(arb_poly_t dest, const arb_poly_t src, slong n, slong prec)
+
+    Sets *dest* to a copy of *src*, truncated to length *n* and rounded to *prec* bits.
+
 .. function:: void arb_poly_set_coeff_si(arb_poly_t poly, slong n, slong c)
 
 .. function:: void arb_poly_set_coeff_arb(arb_poly_t poly, slong n, const arb_t c)