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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

Leo Robinson's definition
Adejimi Reply
how is equilibrium defined in financial markets?
Babakura Reply
the concept of it
DALOM
Country A has export sales 20 billion, government purchases 1000billion, business investment is 50 billion, imports are 40billion, and consumption spending is 2000billin. What is the dollar value of GDP ?
Habtamu Reply
what is determination of national income?
Waqar Reply
economic growth
Rukaiya
stock of capital
Rukaiya
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Anil
Y =C+l
Favour
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Tebatso Reply
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explorer Reply
it is a situation in which the supply of an item is exactly equal to it dd .
Ssmith
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Ssmith
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Ssmith
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Tettey
what is quantity2
Deji Reply
An indefinite amount of something.
explorer
what is demand
Kaman Reply
in ordinary sense demand means desire
Khalid
demand in economics means both willingness as well as the ability to purchase a commodity by paying a price an also its actuall purchase
Khalid
what is absolute advantage
Khalid
demand refers to the various quantity of goods and services that consumers are willing and able to purchase at a particular period of time all other things been equal
Dela
The amount of a good or service that consumers are willing to buy at a particular price.
explorer
what is cost pull inflation?
oru
what is utility
oru
what is cost pull inflation?
oru
demand is economic principle referring to a consumer's desire and willingness to pay a price for a specific or service..
Babakura
utility is the among of certisfaction driving from using a comundity
Anas
pull cost of inflation hight population unemployment to some of The country members poor government system
Anas
what is a buffer scheme
Lukong
state the second law of demand and supply
Ahmadou Reply
state the law of diminishing marginal utility
Ahmadou
dt know WATS the answer
Rukundo
mention and explain two Bank I financial institutions and two non baking financial institutions
Onah Reply
wat is demand pull inflation
Tony Reply
Demand-pull inflation is asserted to arise when aggregate demandin an economy outpaces aggregate supply. It involvesinflation rising as real gross domestic product rises and unemployment falls, as the economy moves along the Phillips curve.
kevin
Perfectly elastic demand
Abubakar Reply
this is a form of demand where goods are demanded at a constant price
Rukundo
what inelastic demanding
Koire
demand of any good demanded more after a certain period. if a commodity prices may high and scarcity of that resources.
Anil
cannot demand more
Anil
what is cross-elasticity of demand
Miles Reply
cross elasticity of demand is an economic concept that measures the responsiveness in the quantity demand of one good when a change in price takes place in other good
Mallekha
this is responsiveness quantity demanded keeping other factors constant
Rukundo
what economic growth
Rukundo Reply
conditions of perfect market
NdzAlama Reply
CONDITIONS OF PERFECT MARKET: 1. Perfect competition(PC): no increasing returns, many buyers and sellers, all are price takers, not prices makers. 2. Perfect Information (PI): buyers and sellers know all they need to know about what they are buying and selling to make the right decisions.
Mallekha
3. Complete Markets(CM): no externalities or public goods, no transactions costs, "thick" markets.
Mallekha
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Mohammed
A numerous downsized market that does not meet standards.
LaTasha
A Perfect Market is a numerous downsized market that does not meet standards.
LaTasha
what is a market
Ahmadou
is place where buyers and sellers met together for the purpose of buying and selling of good and services
Babakura
Difference between extinct and extici spicies
Amanpreet Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
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Yasmin
what is the function of carbon nanotubes?
Cesar
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
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Source:  OpenStax, Digital signal processing - dsp. OpenStax CNX. Jan 06, 2016 Download for free at https://legacy.cnx.org/content/col11642/1.38
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