Merge pull request #161 from oscarbenjamin/pr_lerch_phi

Add acb.lerch_phi (Lerch transcendent)

Author: oscarbenjamin

README.md

@@ -133,11 +133,16 @@ CHANGELOG
 
 Next release:
 
+- [gh-161](https://github.com/flintlib/python-flint/pull/161)
+  Add `acb.lerch_phi` to compute the Lerch transcendent.
 - [gh-132](https://github.com/flintlib/python-flint/pull/132)
   Add `fmpz_mpoly` and `fmpq_mpoly` types for multivariate polynomials with
   integer or rational coefficients.
 - [gh-160](https://github.com/flintlib/python-flint/pull/160)
   Add `bits` to `arb` and `acb`, add `log_base` to `arb`.
+- [gh-149](https://github.com/flintlib/python-flint/pull/149)
+  Bump Flint version to 3.1.3-p1 (Flint 3.0.0 - 3.1.3-p1 is supported but the
+  wheels are built with 3.1.3-p1).
 - [gh-148](https://github.com/flintlib/python-flint/pull/148)
   Remove debug symbols to make smaller Linux binaries.
 - [gh-144](https://github.com/flintlib/python-flint/pull/144)
@@ -150,9 +155,6 @@ Next release:
   Add `erfinv` and `erfcinv` for `arb`.
 - [gh-129](https://github.com/flintlib/python-flint/pull/129)
   Use meson-python instead of setuptools as the build backend.
-- [gh-125](https://github.com/flintlib/python-flint/pull/125)
-  Bump Flint version to 3.1.2 (Flint 3.0.0 - 3.1.2 is supported but the wheels
-  are built with 3.1.2).
 
 0.6.0
 

src/flint/types/acb.pyx

@@ -733,6 +733,21 @@ cdef class acb(flint_scalar):
             acb_hurwitz_zeta((<acb>u).val, (<acb>s).val, (<acb>a).val, getprec())
             return u
 
+    def lerch_phi(z, s, a):
+        """
+        Lerch transcendent `\Phi(z,s,a)`.
+
+            >>> from flint import showgood
+            >>> showgood(lambda: acb(1,2).lerch_phi(3, 4), dps=25)
+            0.006872751459699249251487346 + 0.01112535314686351879432212j
+        """
+        s = any_as_acb(s)
+        a = any_as_acb(a)
+        u = acb.__new__(acb)
+        acb_dirichlet_lerch_phi((<acb>u).val, (<acb>z).val, (<acb>s).val, (<acb>a).val, getprec())
+        return u
+
+
     def dirichlet_l(s, chi):
         cdef dirichlet_char cchar
         if isinstance(chi, dirichlet_char):