RF: Move sigpy to an extra optional dependency

.github/workflows/push_pr.yml

@@ -39,4 +39,10 @@ jobs:
         shell: bash -l {0}
         run: |
           pip install .
+          pytest -m "not matlab_seq_comp and not sigpy" pypulseq/tests
+      - name: Run pytest[sigpy]
+        shell: bash -l {0}
+        run: |
+          pip install .[sigpy]
           pytest -m "not matlab_seq_comp" pypulseq/tests
+        continue-on-error: true

README.md

@@ -44,6 +44,8 @@ PyPulseq is available on the python Package Index [PyPi](https://pypi.org/projec
 
 `pip install pypulseq`
 
+To use the [sigpy](https://sigpy.readthedocs.io/en/latest/) functionality of `make_sigpy_pulse.py` run `pip install pypulseq[sigpy]` to install the required dependencies and enable this functionality.
+
 The latest features and minor bug fixes might not be included in the latest release version. If you want to use the bleeding edge version of PyPulseq, you can install it directly from the development branch of this repository using the command
 
 `pip install git+https://github.com/imr-framework/pypulseq@dev`

pypulseq/__init__.py

@@ -34,7 +34,6 @@ def round_half_up(n, decimals=0):
 from pypulseq.make_arbitrary_grad import make_arbitrary_grad
 from pypulseq.make_arbitrary_rf import make_arbitrary_rf
 from pypulseq.make_block_pulse import make_block_pulse
-from pypulseq.make_sigpy_pulse import *
 from pypulseq.make_delay import make_delay
 from pypulseq.make_digital_output_pulse import make_digital_output_pulse
 from pypulseq.make_extended_trapezoid import make_extended_trapezoid