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28554 Scalar Field Restrictions gh-DeRhamSource "How is a scalar field implemented which is piecewisely defined with different expressions in one particular chart?
Take for instance a scalar field `f` on the real line with standard ""top"" chart `x`, defined via `f(x)=0 for x<-1`, `f(x)=x+1 for -1<=x<0`, `f(x)=1-x for 0<=x<1` and `f(x)=0 for x>=1`. Currently, this is solved by using
{{{
f = M.scalar_field( unit_step(x + 1)*unit_step(1 - x)*(1 - abs(x)) )
}}}
(see https://trac.sagemath.org/ticket/28519#comment:46).
This solution is quite unhandy and becomes even more so for more complicated scalar fields.
This ticket is part of the metaticket #28519.
**This ticket includes:**
- `display` method modified in such a way that all distinct expressions are shown (a small slowdown in computation time)
- `set_restriction` method added smilar to tensor fields" enhancement closed major sage-9.0 geometry fixed manifolds, scalar fields tscrim egourgoulhon Michael Jung Eric Gourgoulhon N/A a126d9187fed8552fd14351248f54704dac26737 a126d9187fed8552fd14351248f54704dac26737