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End of the ImgMod30 class

Listing 4 also signals the end of the class definition for the class named ImgMod30.

The program named ImgMod31

The purpose of this program is to exercise and to test the 2D Fourier transform methods and the axis shifting method provided by the class namedImgMod30.

Command line parameters

The main method in this class reads two command line parameters and uses them to select:

  • A specific case involving a particular 3D input surface in the space domain.
  • A specific display format.

Forward and inverse Fourier transforms

The program performs a 2D Fourier transform on that surface followed by an inverse 2D Fourier transform. Six different plots are produced in this processshowing different aspects of the transform and the inverse transform.

Fourteen cases

There are 14 different cases built into the program with case numbers ranging from 0 to 13 inclusive. Each of the cases is designed such that the results ofthe analysis should be known in advance by a person familiar with 2D Fourier analysis and the wavenumber domain. Thus, these cases can be used to confirmthat the transform code was properly written.

The cases are also designed to illustrate the impact of various space domain characteristics on the wavenumber spectrum. This information will be usefullater when analyzing the results of performing 2D transforms on photographic images for example.

A stack of output images

Each time the program is run, it produces a stack of six output images in the top-left corner of the screen. A brief description of each of the outputimages is provided in the following list. The top-to-bottom order of the stack is:

  1. Space domain output of inverse Fourier transform. Compare with original input in 6 below.
  2. Amplitude spectrum in wavenumber domain with shifted origin. Compare with 5 below.
  3. Imaginary wavenumber spectrum with shifted origin.
  4. Real wavenumber spectrum with shifted origin.
  5. Amplitude spectrum in wavenumber domain without shifted origin. Compare with 2 above.
  6. Space domain input data. Compare with 1 above.

To view the images near the bottom of the stack, you must physically move those on top to get them out of the way.

Numeric output

In addition, the program produces some numeric output on the command line screen that may be useful in confirming the validity of the forward and inversetransform processes. Figure 2 shows an example of the numeric output.

Figure 2. Numeric output.
height = 41 width = 41height = 41 width = 412.0 1.9999999999999916 0.5000000000000002 0.499999999999998450.49999999999999956 0.4999999999999923 1.7071067811865475 1.70710678118655260.2071067811865478 0.20710678118654233 0.20710678118654713 0.207106781186554351.0 1.0000000000000064 -0.4999999999999997 -0.49999999999999484-0.5000000000000003 -0.4999999999999965

(Note that I manually inserted some and spaces line breaks in Figure 2 to cause the numeric values to line up in columns so as to be morereadable.)

The size of the surfaces

The first two lines of numeric output in Figure 2 show the size of the spatial surface for the forward transform. The second two lines show the size ofthe wavenumber surface for the inverse transform.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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