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IMP Reference Guide
2.20.0
The Integrative Modeling Platform
IMP Manual
Reference Guide
Tutorial Index
Modules
Classes
Examples
version 2.20.0
pmi/ideal_helix.py
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## \example pmi/ideal_helix.py
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"""Short example demonstrating ideal helices in PMI
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"""
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import
IMP
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import
IMP.atom
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import
IMP.rmf
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import
IMP.pmi
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import
IMP.pmi.topology
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import
IMP.pmi.dof
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import
IMP.pmi.macros
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import
IMP.pmi.restraints
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import
sys
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IMP.setup_from_argv
(sys.argv,
"Demonstration of ideal helices"
)
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# Create System and State
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mdl =
IMP.Model
()
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s =
IMP.pmi.topology.System
(mdl)
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st = s.create_state()
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# Create a molecule and add helix representation
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# this makes a c-alpha chain in approximately the shape of a helix
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mol = st.create_molecule(
"example_helix"
, sequence=
'A'
*20, chain_id=
'A'
)
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mol.add_representation(mol,
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resolutions=[1, 10],
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ideal_helix=
True
)
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hier = s.build()
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# write a single-frame RMF to view the helix
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out =
IMP.pmi.output.Output
()
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out.init_rmf(
"example_helix.rmf3"
, hierarchies=[hier])
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out.write_rmf(
"example_helix.rmf3"
)