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(The color black could also be dedicated to identifying the lowest elevation in the design of the Color Contour plot, in which case, bothschemes would be equal in this regard.)

As we learned earlier, the lowest elevation occurs at four different points on the surface, and those points are near the corners.

The elevation of the valleys

Both plots show that while the valleys between the central and minor peaks are very deep, they aren't quite as deep as the lowest elevation. They are bluein the Color Shift plot and gray in the Color Contour plot. Because the gray color represents a somewhat smaller elevation range in the Color Contour plotthan the blue represents in the Color Shift plot, the elevation of the valley is defined more accurately in the Color Contour plot.

A logarithmic conversion

Sometimes when plotting data, it is useful to plot the logarithm of the data values instead of the raw values.

(For many years, engineers have plotted data on graph paper referred to either as semi-log paper or log-log paper. Each type of graph paper hasadvantages and disadvantages relative to the other type and also has advantages and disadvantages relative to linear graph paper. This programprovides a capability that is analogous to the use of semi-log paper but in a 3D sense.)

Flattens the plot

The use of semi-log paper has the effect of flattening the plot in the 2D case, or flattening the surface in the 3D case. The semi-log approach tends topull the structure of the low-level values up so that they can be better observed. The logarithm of the low elevations is closer to the maximum elevationthan is the raw value of the low elevations.

More sample output

The three images in the top row of Figure 2 are reproductions of the three images in Figure 1 . They were included in Figure 2 for comparison with the bottom three images in Figure 2 .

Figure 2 . Sample output with logarithmic flattening.
Missing Figure.

The bottom three images in Figure 2 were produced in exactly the same way as the top three images except that prior to creating the image the elevationvalues for the surface were converted to the log base 10 of the raw elevation values.

Six different formats

Thus, Figure 2 shows the same 3D surface plotted using six different plotting formats. Going from left to right and top to bottom, the six images illustrate:

  • Grayscale (linear)
  • Color Shift (linear)
  • Color Contour (linear)
  • Grayscale with logarithmic data flattening
  • Color Shift with logarithmic data flattening
  • Color Contour with logarithmic data flattening

Isolates the location of the minima

The significance of the logarithmic conversion can be seen by comparing the two images on the right side of Figure 2 . When the raw elevation values were quantized into 23 levels, quite a few of the elevation values were quantizedinto the minimum value as indicated by the black areas in the top image.

However, after converting the elevation values to logarithmic values, only four points quantized to the minimum value as indicated by the four small blacksquares in the bottom right image. Thus, the top image on the right shows the general area of the lowest elevations on the surface whereas the bottom image onthe right clearly identifies the exact location of each of the four lowest elevations.

Questions & Answers

what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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