add sudo.

.travis.yml

@@ -137,15 +137,16 @@ jobs:
   - stage: bionic
     dist: bionic
     before_install:
-    - apt-get -y install python3-minimal python3-pip python3-numpy
-    - pip3 install numpy
-    - apt-get -y install wget
+    - sudo apt-get -y install python3-minimal python3-pip python3-numpy
+    - sudo pip3 install --system numpy
+    # need to build boost-python from source for python 3 (repository package is built for python 2)
+    - sudo apt-get -y install wget
     - wget https://sourceforge.net/projects/boost/files/boost/1.67.0/boost_1_67_0.tar.gz
     - tar -xf boost_1_67_0.tar.gz && cd boost_1_67_0
     - ./bootstrap.sh --with-libraries=python --with-python=/usr/bin/python3
-    - ./b2 install
-    - apt-get install locate
-    - updatedb
+    - sudo ./b2 install
+    - sudo apt-get install locate
+    - sudo updatedb
     script: mkdir -p build && cd build && cmake -DEXAMPLES=ON -DICB=ON -DMPI=ON -DPYTHON3=ON -DBOOST_PYTHON_LIBSUFFIX='36' .. && export VERBOSE=1 && make all && make test
   # bionic <=> coverage: "recent" systems with ICB
   - stage: coverage
@@ -175,8 +176,8 @@ jobs:
     dist: bionic
     before_install:
     - export DEBIAN_FRONTEND=noninteractive
-    - apt-get -y install dialog
-    - echo yes | apt-get -y install intel-mkl libmkl-dev
+    - sudo apt-get -y install dialog
+    - echo yes | sudo apt-get -y install intel-mkl libmkl-dev
     script: |
       ./bootstrap                                                                                                 && \
       export FFLAGS='-DMKL_ILP64 -I/usr/include/mkl'                                                              && \