From 43cecc3779dff8479ea0384981b61e20695a5a60 Mon Sep 17 00:00:00 2001
From: Alice <alice.mazzoleni@psi.ch>
Date: Tue, 6 Oct 2026 16:05:10 +0200
Subject: [PATCH] updated read_columns in python

---
 include/aare/JungfrauDataFile.hpp |  2 +-
 python/src/jungfrau_data_file.hpp | 11 +++++++++--
 src/JungfrauDataFile.cpp          |  3 ++-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/include/aare/JungfrauDataFile.hpp b/include/aare/JungfrauDataFile.hpp
index a84b5da1..dc904861 100644
--- a/include/aare/JungfrauDataFile.hpp
+++ b/include/aare/JungfrauDataFile.hpp
@@ -68,7 +68,7 @@ class JungfrauDataFile : public FileInterface {
      * @pre column_indices must be sorted in ascending order
      * @return Frame containing the columns at the current frame
      */
-    Frame read_columns(const std::vector<size_t> column_indices);
+    Frame read_columns(const std::vector<size_t> &column_indices);
 
     std::vector<Frame> read_n(size_t n_frames = 0) override;
     void read_into(std::byte *image_buf) override;
diff --git a/python/src/jungfrau_data_file.hpp b/python/src/jungfrau_data_file.hpp
index ae8bc54b..a215b7f6 100644
--- a/python/src/jungfrau_data_file.hpp
+++ b/python/src/jungfrau_data_file.hpp
@@ -81,8 +81,15 @@ void define_jungfrau_data_file_io_bindings(py::module &m) {
         .def(
             "read_columns",
             [](JungfrauDataFile &self,
-               const std::vector<size_t> column_indices) {
-                return self.read_columns(column_indices);
+               const std::vector<size_t> &column_indices) {
+                auto frame = new Frame(self.read_columns(column_indices));
+                return py::array_t<uint16_t>(
+                    {frame->rows(), frame->cols()},
+                    {frame->cols() * sizeof(uint16_t), sizeof(uint16_t)},
+                    reinterpret_cast<uint16_t *>(frame->data()),
+                    py::capsule(frame, [](void *ptr) {
+                        delete reinterpret_cast<Frame *>(ptr);
+                    }));
             },
             R"(
             Read the columns at the current frame.
diff --git a/src/JungfrauDataFile.cpp b/src/JungfrauDataFile.cpp
index d876037c..3fe5c3d3 100644
--- a/src/JungfrauDataFile.cpp
+++ b/src/JungfrauDataFile.cpp
@@ -35,7 +35,8 @@ Frame JungfrauDataFile::read_frame(size_t frame_number) {
     return f;
 }
 
-Frame JungfrauDataFile::read_columns(const std::vector<size_t> column_indices) {
+Frame JungfrauDataFile::read_columns(
+    const std::vector<size_t> &column_indices) {
 
     Frame f(rows(), column_indices.size(), Dtype::UINT16);