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TestIdeals :: isFinjective(..., IsLocal => ...)

isFinjective(..., IsLocal => ...) -- controls whether F-injectivity is checked at the origin or everywhere

Synopsis

Description

If you set the option IsLocal => true (default false) it will only check F-injectivity at the origin. Otherwise it will check it everywhere. Note checking at the origin can be slower than checking it everywhere. Consider the example of the following non-F-injective ring.

i1 : R = ZZ/5[x,y,z]/ideal( (x-1)^4 + y^4 + z^4 );
i2 : isFinjective(R)

o2 = false
i3 : isFinjective(R, IsLocal=>true)

o3 = true

Further information