[1.3] Importing the state_vector_exercise results in an error

[oevers]

Describe the bug

Importing the state_vector_exercise results in an error

Run the code in this cell to interact with the widget

from qiskit_textbook.widgets import state_vector_exercise
state_vector_exercise(target=1/3)

Results in the following:

---

ModuleNotFoundError Traceback (most recent call last)
in
1 # Run the code in this cell to interact with the widget
----> 2 from qiskit_textbook.widgets import state_vector_exercise
3 state_vector_exercise(target=1/3)

~/opt/anaconda3/envs/qiskit_env/lib/python3.8/site-packages/qiskit_textbook/widgets/init.py in
5 from qiskit.visualization import plot_bloch_vector
6 from numpy import sqrt, cos, sin, pi
----> 7 import numexpr
8 import re
9

ModuleNotFoundError: No module named 'numexpr'

To Reproduce

Run the textbook in anaconda in an environment with qiskit and the textbook installed as described here https://qiskit.org/textbook/ch-prerequisites/setting-the-environment.html

Expected behavior

widget should come up without errors

Version info

Version Information

Qiskit Software	Version
qiskit-terra	0.18.3
qiskit-aer	0.9.1
qiskit-ignis	0.6.0
qiskit-ibmq-provider	0.17.0
qiskit	0.31.0
qiskit-nature	0.2.2
qiskit-finance	0.2.1
qiskit-optimization	0.2.3
qiskit-machine-learning	0.2.1

Python | 3.8.12 (default, Oct 12 2021, 06:23:56) [Clang 10.0.0 ]
OS | Darwin
CPUs | 6
Memory (Gb) | 16.0
Sat Dec 18 21:20:42 2021 CET

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Additional context

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[oevers]

It turned out that numexpr wasn't installed in my environment
once I did a pip install numexpr in a cell before calling the widget, things started working.
The question is now why is numexpr not a prereq for the qiskit_textbook so that it gets installed as a prereq by pip?

[paniash]

How did you install the textbook? If you notice in requirements.txt, the numexpr package exists, so it should have been installed as a dependency.

[oevers]

I believe I did a standard pip install a few months ago, so will have been somewhat backlevel compared to what is current now. Has the requirement.txt changed? Could it have been bypassed?

[paniash]

Migrated to a discussion since the issue has been rectified.