update ci.yml

.gitlab-ci.yml

@@ -29,12 +29,17 @@ default:
     - apt-get install -y --no-install-recommends texlive-latex-extra
     - apt-get install -y --no-install-recommends dvipng
     - apt-get clean
+    - pip install virtualenv
+    - virtualenv venv
+    - source venv/bin/activate
+    - pip install matplotlib numpy scipy six nose coverage
 
 install_and_test_39:
   image: python:3.9
   script:
     - dpkg -L python3-pytest | xargs file | grep executable
     - pip3 install -e . --no-deps
+    - py.test-3
     - python3 -m pytest
   artifacts:
     when: always