Hey there! Sorry to hear you're stuck installing NumPy on Ubuntu 17 with Python 3—let's work through this together. Here are some common fixes that usually resolve these kinds of installation issues:

1. Refresh system packages and install build essentials #

Missing system dependencies are the #1 cause of NumPy install failures, since it relies on C extensions to compile. Run these commands first to cover the basics:

sudo apt update
sudo apt install build-essential python3-dev python3-pip

The python3-dev package includes critical header files for building Python modules, so don't skip this step.

2. Upgrade pip to the latest version #

Outdated pip often causes weird installation glitches. Upgrade it with this command:

pip3 install --upgrade pip

If you hit a permission error (common on system-wide Python installs), add --user to install it only for your account (no sudo needed):

pip3 install --upgrade pip --user

3. Reinstall NumPy with updated pip #

Now give the installation another shot with the refreshed pip:

pip3 install numpy

Again, use --user if you run into permission issues:

pip3 install numpy --user

4. Fall back to Ubuntu's repository version #

If pip still won't cooperate, you can install the version packaged directly with Ubuntu 17. It might not be the absolute latest NumPy release, but it's guaranteed to be compatible with your system:

sudo apt install python3-numpy

5. Check for conflicting Python environments #

If you use virtual environments or have multiple Python versions installed, make sure you're targeting the right one. Run these commands to verify your paths match:

which python3
which pip3

They should point to the same Python 3 installation. If not, activate your intended virtual environment or adjust your system PATH to prioritize the correct version.

6. Share the exact error message (if none of the above works) #

If you're still getting errors, paste the full output from your terminal. Common issues include missing linear algebra libraries (like libopenblas-dev or liblapack-dev) or version conflicts, and the error text will help us pinpoint the exact problem.

内容的提问来源于stack exchange，提问作者Koi