Arrays index in Basic4ppc always start from 0.
It is better to declare the arrays as Double in Basic4ppc because all internal calculations are done with this type.
B4X:
Sub Globals
Dim tabCos(721) As Double
Dim tabSin(721) As Double
End Sub
Sub App_Start
For i = -360 To 360 Step 1
tabCos(360 + i) = Sin((i/180) * cPi) 'cPi is a constant (3.1415...)
tabSin(360 + i) = Cos((i/180) * cPi)
Next
End Sub