We differ in the full mnp description. Look at n. M is the same between us, but the coke can example has me wondering.

As far as n or p go, I'm not even going to look at them until I get some feedback about the m discrepancies....

....Here are my results.Resolution number of time steps resonant frequency Q error 1 2 none detected 2 4 none detected 3 6 none detected 4 8 none detected 5 10 1.84921E+009 negative 2 e-4 10 20 1.85128E+009 negative 2 e-4 20 40 1.86441E+009 ~ 500 6 e-4 40 80 1.87262E+009 ~ 1200 3 e-4 80 160 1.86992E+009 ~ 300 13 e-4 160 320 1.87042E+009 ~ 80 47 e-4 The detected frequency bounces around consistently with the error which can be taken as estimating the number of significant digits of the frequency detected. The quality is very low. I take that to be a result of the cavity dimensions being incorrect for the resonant frequency detected as they are also incorrect for the drive frequency.....

So is the m resolved because the KWOK modes were so close but no cigar together? That's my hunch, but I want verify before I let it go. Lesson learned.....don't round off when it comes to mode shapes then?

Quote from: aero on 01/24/2015 09:03 PM....Here are my results.Resolution number of time steps resonant frequency Q error 1 2 none detected 2 4 none detected 3 6 none detected 4 8 none detected 5 10 1.84921E+009 negative 2 e-4 10 20 1.85128E+009 negative 2 e-4 20 40 1.86441E+009 ~ 500 6 e-4 40 80 1.87262E+009 ~ 1200 3 e-4 80 160 1.86992E+009 ~ 300 13 e-4 160 320 1.87042E+009 ~ 80 47 e-4 The detected frequency bounces around consistently with the error which can be taken as estimating the number of significant digits of the frequency detected. The quality is very low. I take that to be a result of the cavity dimensions being incorrect for the resonant frequency detected as they are also incorrect for the drive frequency.....Aero, please tell me again exactly what is the actual numerical value that you actually inputed into MEEP for the drive frequency for the above calculations. What is the number that you inputed into MEEP.

Drive frequency 2.45 E+9 Hz, so wavelength = 0.1223642686 meters.Geometry actual inside dimensions L= 0.1223642686, Dia = 0.0754898000 meters air filled cylindrical cavity with no dielectric. I am ignoring the difference between speed of light in air and vacuum.I copied those numbers straight from the control file. This is what I used.

Quote from: Rodal on 01/25/2015 02:15 PMQuote from: aero on 01/24/2015 09:03 PM....Here are my results.Resolution number of time steps resonant frequency Q error 1 2 none detected 2 4 none detected 3 6 none detected 4 8 none detected 5 10 1.84921E+009 negative 2 e-4 10 20 1.85128E+009 negative 2 e-4 20 40 1.86441E+009 ~ 500 6 e-4 40 80 1.87262E+009 ~ 1200 3 e-4 80 160 1.86992E+009 ~ 300 13 e-4 160 320 1.87042E+009 ~ 80 47 e-4 The detected frequency bounces around consistently with the error which can be taken as estimating the number of significant digits of the frequency detected. The quality is very low. I take that to be a result of the cavity dimensions being incorrect for the resonant frequency detected as they are also incorrect for the drive frequency.....Aero, please tell me again exactly what is the actual numerical value that you actually inputed into MEEP for the drive frequency for the above calculations. What is the number that you inputed into MEEP.Drive frequency 2.45 E+9 Hz, so wavelength = 0.1223642686 meters.Geometry actual inside dimensions L= 0.1223642686, Dia = 0.0754898000 meters air filled cylindrical cavity with no dielectric. I am ignoring the difference between speed of light in air and vacuum.I copied those numbers straight from the control file. This is what I used.

Moreover, since c = 1 in Meep units, a (or a / c) is our unit of time as well. In particular, the frequency f in Meep (corresponding to a time dependence e − i2πft) is always specified in units of c / a

...Geometry actual inside dimensions L= 0.1223642686, Dia = 0.0754898000 meters air filled cylindrical cavity with no dielectric. I am ignoring the difference between speed of light in air and vacuum.Scale factor, 0.01, but is a parameter to adjustThe above gives geometry simulation dimensions in scaled units = 012.23642686, 007.54898000...

susceptibilityParent class for various dispersive susceptibility terms, parameterized by an anisotropic amplitude σ (see Material dispersion in Meep):sigma [number]The scale factor σ.

In particular, because Maxwell's equations are scale invariant (multiplying the sizes of everything by 10 just divides the corresponding solution frequencies by 10), it is convenient in electromagnetic problems to choose scale-invariant units (see our online textbook, ch. 2). That means that we pick some characteristic lengthscale in the system, a, and use that as our unit of distance.

The scale factor, also known as characteristic length - "we pick some characteristic lengthscale in the system, a, and use that as our unit of distance." Or, more detailed, from "Units in Meep" here; http://ab-initio.mit.edu/wiki/index.php/Meep_IntroductionQuoteIn particular, because Maxwell's equations are scale invariant (multiplying the sizes of everything by 10 just divides the corresponding solution frequencies by 10), it is convenient in electromagnetic problems to choose scale-invariant units (see our online textbook, ch. 2). That means that we pick some characteristic lengthscale in the system, a, and use that as our unit of distance.

Quote from: aero on 01/25/2015 06:24 PMThe scale factor, also known as characteristic length - "we pick some characteristic lengthscale in the system, a, and use that as our unit of distance." Or, more detailed, from "Units in Meep" here; http://ab-initio.mit.edu/wiki/index.php/Meep_IntroductionQuoteIn particular, because Maxwell's equations are scale invariant (multiplying the sizes of everything by 10 just divides the corresponding solution frequencies by 10), it is convenient in electromagnetic problems to choose scale-invariant units (see our online textbook, ch. 2). That means that we pick some characteristic lengthscale in the system, a, and use that as our unit of distance. It unnecessarily complicates things at this point, it presents extra problems of interpretation -- I would not use it until you have exactly matched the exact solution. If you must, use Scale Factor =1, for the time being: if you input to MEEP L= 0.1223642686 (meters), Dia = 0.0754898000 (meters), then the MEEP frequency should be as per my previous post in 8.77064 1/meters units. (And you should interpret the output in 1/meters frequency units as well)If instead you input L = 12.23642686, D= 7.54898000 you are effectively using centimeters as your input unit of length, and therefore your MEEP frequency should be input in 1/cm units, giving MEEP Frequency = 0.0877064 1/centimeter, and you would have to multiply the output frequencies by cVacuum = 29979245800 centimeter/second to express the output in Hz. Unnecessarily messy at this point.

Quote from: Rodal on 01/25/2015 06:30 PMQuote from: aero on 01/25/2015 06:24 PMThe scale factor, also known as characteristic length - "we pick some characteristic lengthscale in the system, a, and use that as our unit of distance." Or, more detailed, from "Units in Meep" here; http://ab-initio.mit.edu/wiki/index.php/Meep_IntroductionQuoteIn particular, because Maxwell's equations are scale invariant (multiplying the sizes of everything by 10 just divides the corresponding solution frequencies by 10), it is convenient in electromagnetic problems to choose scale-invariant units (see our online textbook, ch. 2). That means that we pick some characteristic lengthscale in the system, a, and use that as our unit of distance. It unnecessarily complicates things at this point, it presents extra problems of interpretation -- I would not use it until you have exactly matched the exact solution. If you must, use Scale Factor =1, for the time being: if you input to MEEP L= 0.1223642686 (meters), Dia = 0.0754898000 (meters), then the MEEP frequency should be as per my previous post in 8.77064 1/meters units. (And you should interpret the output in 1/meters frequency units as well)If instead you input L = 12.23642686, D= 7.54898000 you are effectively using centimeters as your input unit of length, and therefore your MEEP frequency should be input in 1/cm units, giving MEEP Frequency = 0.0877064 1/centimeter, and you would have to multiply the output frequencies by cVacuum = 29979245800 centimeter/second to express the output in Hz. Unnecessarily messy at this point.It doesn't work that way. I input units in meters, and the scale factor. The input is scaled, then the output that I gave you is "unscaled" to be in SI units. But yes, I can run meep with a scale factor of 1. It gives the same answers but takes more CPU so the runs are longer. Not to bad for this simple 1D calibration problem though.Here is an example using resolution = 1200, which is quite low resolution.frequency quality factor error1.86060E+009 37934.0653626318 7.872026063658947e-6+0.0i Had I used this scale factor and geometry to generate 2D images of the developing fields, it would take about 12 hours computer run time, per meep estimate. Generating those images using a scale factor of 0.01 takes about 45 minutes as I recall.

No it's not, that resolution is likely somewhere between these lines. 10 20 1.85128E+009 negative 2 e-4 20 40 1.86441E+009 ~ 500 6 e-4 40 80 1.87262E+009 ~ 1200 3 e-4that I posted 2 pages back.And no I don't. The meep input frequency must be in the same dimensional units as the geometry, I use SI units.I have made progress though. Using the frequency formula to adjust cavity length so that the formula gave 2.45GHz, required a cavity length about 0.0965 meters. Iteratively running meep and adjusting the cavity length to force resonance at 2.45 GHZ independently produced a cavity length of 0.0936 meters. I emphasize that I worked those problems independently of each other so the fact that they are in near agreement is telling. I would like to find a combination length and radius that would give the frequency without the length being so close to 3/4 wavelength. In fact, I would like for the length to be exactly one wavelength and for which I knew the mode. TE 1,1,1 would be good, but TE 1,4,1 might also work. Maybe now that I have found one solution, I can find more solutions.

My input frequency is converted to meep units in the control file, meep frequency = 0.08172320332354725. That is scaled by the 0.01 factor. But that is not an input. The input is frequency in SI units. The conversion is scale factor/c so I guess the units would be 1/meter internally.It's difficult for me to come up with 8.77064 1/meters though. That is your 2.63 GHz number and I've not seen it in any of my meep runs that I recall.