Dear Steven and Meep users, The geometry for my case is a tapered cone (axis (1 0 0)). It is easy to see from the PNG file whether or not the geometry resulting from (set! symmetries (list (make ... is symmetric or not.
I have found that the geometry resulting from (make mirror-sym (direction Y )) is symmetric, also (make rotate2-sym (direction X )) gives symmetric geometry but, (make rotate4-sym (direction X )) displays only half the cone. The fields must be considered. When I run with default phase the Ez field appears to be correct for mirror-sym, but it is not correct with rotate2-sym . This is expected as the default phase is +1. When I set the phase switch (phase -1) or even (phase 1) Guile throws an error, ERROR: Wrong type (expecting exact integer): #f With the rotate4-sym setting it is impossible to tell whether or not the fields are symmetric from only half the geometry. You may note that the one case that works is mirror-sym with the direction Y, when the Geometric axis of symmetry is X. If anyone wants to play with symmetry, feel free to use my SCHEME test file, attached.
(reset-meep) (define-param c 299792458.) ; Speed of light (define-param meple 1.0e-2) ; Characteristic length 0.15943 .024 ; Signal parameters - SI units (define-param freq 1880.4e+6) ; Frequency (1880.4MHz claimed) (define-param waveling (/ c freq)) ; Wavelength, ~0.159 m ; ------------------ Set the lattice and coordinate system (set! geometry-lattice (make lattice (size 20 20 no-size) )) (set! pml-layers (list (make pml (thickness 1.0)))) (set! resolution 20) (display "signal parameters")(newline) ; Signal Parameters in Meep units (define mple_c 1) ; Speed of light = 1 in Meep (define mple_t (/ meple c)) ; Time (define-param mple_f (* freq mple_t)) ; Source Frequency (define-param mple_f (/ meple waveling)) ; Source Frequency (newline) (print " frequency = ") (display freq) (newline) (print " mple_f = ") (display mple_f) (newline) (print " mple_t = ") (display mple_t) (newline) (print " meple = ") (display meple) (newline) (display "set geometry") (newline) (set! geometry (list ; Start of Geometry ; A tapered tin can. (make cone (center 0 0 0) (radius 5) (radius2 2) (height 8.5) (material metal) (axis 1 0 0) ) (make cone (center 0 0 0) (radius 4.97) (radius2 1.97) (height 8.497) (material air) (axis 1 0 0) ) )) (display "set source" ) (newline) (set! sources (list (make source ; ******Continuous source******* (src (make continuous-src (frequency mple_f) (end-time 200))) (component Ez) (center 0 0 ) ))) (display "set symmetries") (newline) (set! symmetries (list ; ******** Symmetry ********** ; * (make rotate4-sym (direction X )) ; (phase -1) ;defaults to +1 * ; ERROR: Wrong type (expecting exact integer): #f ; * )) ; ***************** (display "Continuous 1, RUNing Continuous source") (newline) (run-until 10 ; ******* RUN Continuous source **** (at-beginning output-epsilon) (at-end output-efield-z)) (newline) (display "DONE") (newline)(newline) (quit) ; h5topng ./sym-eps-000000.00.h5 ; h5topng -S1 -Zc dkbluered -a yarg -A ./sym-eps-000000.00.h5 ./sym-ez-000010.00.h5
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