Noo module named slycot

[nilsmelchert]

Hi,
I recently tried to install slycot via pip. Before that I installed the following dependencies:

• pip install cmake
• pip install scikit-build
• sudo apt-get install libopenblas-dev

Everything installs without any errors, but when I am trying to import slycot, I get the following error message:

ModuleNotFoundError: No module named 'slycot'

Am I missing something?

[moorepants]

pip install cmake

Probably isn't doing what you think it should. You should apt install cmake.

[moorepants]

I take that back. It actually seems like cmake is packaged for installation via pypi: https://pypi.org/project/cmake/

[nilsmelchert]

I also tried to install slycot from source which leads to the same issue.
Cmake is of course installed on my system.

[moorepants]

Are you sure you have installed the package into a directory that is on your path? Are you trying to import from the same Python executable that the package was installed alongside?

[jgspiro]

I fixed that, because I had the same issue : #62

[nilsmelchert]

Thanks for that PR. When are the sources released on Pypi?

…

Am 20.05.2019 um 10:32 schrieb jgspiro ***@***.***>: I fixed that, because I had the same issue : #62 — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[roryyorke]

I don't think we've fixed this. It's related to #3, and is at least partly addressed by #64.

[roryyorke]

Ah-ha; the files have been installed in "slycot" off the virtual-env root, rather than in site-packages; I remember this happening on Windows when I was trying to build wheels there, but I thought it was a peculiarity of that environment. The result below is from an Ubuntu 18.04 system.

If anyone knows why this would happen, please speak up. Do we need to teach scikit-build or CMake about the "normal" install directories, maybe?

(slycot-via-pip) rory@rory-latitude:~$ pip show -f slycot
Name: slycot
Version: 0.3.4
Summary: Slycot: a wrapper for the SLICOT control and systems library
Home-page: https://github.com/python-control/Slycot
Author: Enrico Avventi et al.
Author-email: None
License: GPL-2.0
Location: /home/rory/.miniconda3/envs/slycot-via-pip/lib/python3.7/site-packages
Requires: 
Required-by: 
Files:
  ../../../slycot/__init__.py
  ../../../slycot/__pycache__/__init__.cpython-37.pyc
  ../../../slycot/__pycache__/analysis.cpython-37.pyc
  ../../../slycot/__pycache__/examples.cpython-37.pyc
  ../../../slycot/__pycache__/math.cpython-37.pyc
  ../../../slycot/__pycache__/synthesis.cpython-37.pyc
  ../../../slycot/__pycache__/transform.cpython-37.pyc
  ../../../slycot/__pycache__/version.cpython-37.pyc
  ../../../slycot/_wrapper.so
  ../../../slycot/analysis.py
  ../../../slycot/examples.py
  ../../../slycot/math.py
  ../../../slycot/synthesis.py
  ../../../slycot/tests/__init__.py
  ../../../slycot/tests/__pycache__/__init__.cpython-37.pyc
  ../../../slycot/tests/__pycache__/test.cpython-37.pyc
  ../../../slycot/tests/__pycache__/test_sg02ad.cpython-37.pyc
  ../../../slycot/tests/__pycache__/test_sg03ad.cpython-37.pyc
  ../../../slycot/tests/__pycache__/test_tb05ad.cpython-37.pyc
  ../../../slycot/tests/__pycache__/test_td04ad.cpython-37.pyc
  ../../../slycot/tests/test.py
  ../../../slycot/tests/test_sg02ad.py
  ../../../slycot/tests/test_sg03ad.py
  ../../../slycot/tests/test_tb05ad.py
  ../../../slycot/tests/test_td04ad.py
  ../../../slycot/transform.py
  ../../../slycot/version.py
  slycot-0.3.4.dist-info/COPYING
  slycot-0.3.4.dist-info/INSTALLER
  slycot-0.3.4.dist-info/METADATA
  slycot-0.3.4.dist-info/RECORD
  slycot-0.3.4.dist-info/WHEEL
  slycot-0.3.4.dist-info/top_level.txt

(slycot-via-pip) rory@rory-latitude:~$ python -c "import sys; print(sys.path)"
['', '/home/rory/.miniconda3/envs/slycot-via-pip/lib/python37.zip', '/home/rory/.miniconda3/envs/slycot-via-pip/lib/python3.7', '/home/rory/.miniconda3/envs/slycot-via-pip/lib/python3.7/lib-dynload', '/home/rory/.miniconda3/envs/slycot-via-pip/lib/python3.7/site-packages']

[roryyorke]

With the diff below, I can build a wheel (python setup.py bdist_wheel), install it (pip install slycot-0.3.4.9-cp37-cp37m-linux_x86_64.whl), and then import slycot works, and pip show -f slycot is

Name: slycot
Version: 0.3.4.9
Summary: Slycot: a wrapper for the SLICOT control and systems library
Home-page: https://github.com/python-control/Slycot
Author: Enrico Avventi et al.
Author-email: None
License: GPL-2.0
Location: /home/rory/.miniconda3/envs/slycot-via-pip/lib/python3.7/site-packages
Requires: 
Required-by: 
Files:
  slycot-0.3.4.9.dist-info/COPYING
  slycot-0.3.4.9.dist-info/INSTALLER
  slycot-0.3.4.9.dist-info/METADATA
  slycot-0.3.4.9.dist-info/RECORD
  slycot-0.3.4.9.dist-info/WHEEL
  slycot-0.3.4.9.dist-info/top_level.txt
  slycot/__init__.py
  slycot/__pycache__/__init__.cpython-37.pyc
  slycot/__pycache__/analysis.cpython-37.pyc
  slycot/__pycache__/examples.cpython-37.pyc
  slycot/__pycache__/math.cpython-37.pyc
  slycot/__pycache__/synthesis.cpython-37.pyc
  slycot/__pycache__/transform.cpython-37.pyc
  slycot/__pycache__/version.cpython-37.pyc
  slycot/_wrapper.so
  slycot/analysis.py
  slycot/examples.py
  slycot/math.py
  slycot/synthesis.py
  slycot/tests/__init__.py
  slycot/tests/__pycache__/__init__.cpython-37.pyc
  slycot/tests/__pycache__/test.cpython-37.pyc
  slycot/tests/__pycache__/test_sg02ad.cpython-37.pyc
  slycot/tests/__pycache__/test_sg03ad.cpython-37.pyc
  slycot/tests/__pycache__/test_tb05ad.cpython-37.pyc
  slycot/tests/__pycache__/test_td04ad.cpython-37.pyc
  slycot/tests/test.py
  slycot/tests/test_sg02ad.py
  slycot/tests/test_sg03ad.py
  slycot/tests/test_tb05ad.py
  slycot/tests/test_td04ad.py
  slycot/transform.py
  slycot/version.py

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 63b32e0..67973f4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8,6 +8,8 @@ endif()
 
 project(slycot VERSION ${SLYCOT_VERSION} LANGUAGES NONE)
 
+find_package(PythonExtensions REQUIRED)
+
 # Fortran detection fails on windows, use the CMAKE_C_SIMULATE flag to
 # force success
 if(WIN32)
diff --git a/slycot/CMakeLists.txt b/slycot/CMakeLists.txt
index 3207d92..7d8c377 100644
--- a/slycot/CMakeLists.txt
+++ b/slycot/CMakeLists.txt
@@ -3,7 +3,6 @@
 #
 # RvP, 180710
 
-
 set(FSOURCES
 
   src/AB01MD.f src/MA02AD.f src/MB03YT.f src/NF01BW.f src/SB10KD.f
@@ -166,7 +165,7 @@ target_include_directories(
   ${PYTHON_INCLUDE_DIRS}
   )
 
-install(TARGETS ${SLYCOT_MODULE} DESTINATION slycot)
-install(FILES ${PYSOURCE} DESTINATION slycot)
+install(TARGETS ${SLYCOT_MODULE} DESTINATION ${PYTHON_RELATIVE_SITE_PACKAGES_DIR}/slycot)
+install(FILES ${PYSOURCE} DESTINATION ${PYTHON_RELATIVE_SITE_PACKAGES_DIR}/slycot)
 
 add_subdirectory(tests)
diff --git a/slycot/tests/CMakeLists.txt b/slycot/tests/CMakeLists.txt
index c97cb50..7de8521 100644
--- a/slycot/tests/CMakeLists.txt
+++ b/slycot/tests/CMakeLists.txt
@@ -3,4 +3,4 @@ set(PYSOURCE
   __init__.py test.py test_sg02ad.py test_sg03ad.py test_tb05ad.py
   test_td04ad.py)
 
-install(FILES ${PYSOURCE} DESTINATION slycot/tests)
+install(FILES ${PYSOURCE} DESTINATION ${PYTHON_RELATIVE_SITE_PACKAGES_DIR}/slycot/tests)

[roryyorke]

This is fixed in #67, for Linux and (I think) OSX. Hopefully soon available in 0.3.5 (#70).

Please reopen if the bug is still there on 0.3.5.

[bnavigator]

It's not mentioned in #67 but the fix is actually in commit 2e41c2f