Math / Science

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Hi friends,

I have some visualisation project where textual info is displayed on a colored background (that is not disputable). The background color is meant to give a mental shortcut to the value, and it could be basically any color in the 3 byte RGB space. Nevertheless the textual info needs to be easily readable against the background.

I've found some algorithms to generate contrasting colors from background color by inverting (XOR with #FF) the R, G and B bytes of the background color, some with improvements for R/G/B values near 128. Unfortunately these algorithms generate some color combinations which are (to be very, very euphemistic) more insulting to the eye than mere unergonomic .

What I need is some algorithm that produces contrasting, but eye-friendly companion foreground colors out of the values of the background color values. (I'd take ready-to-use code, too ;-)

Any idea ?
Exploring ASP.NET Core: Fundamentals
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Exploring ASP.NET Core: Fundamentals

Learn to build web apps and services, IoT apps, and mobile backends by covering the fundamentals of ASP.NET Core and  exploring the core foundations for app libraries.

Using 0 as a baseline, I am looking to conduct a t-test. In fact, I want to perform a t-test on each of these 10 values. Here are the 10 values in list format. These 10 values correspond to standard deviation. However, I am not sure if I need more information than just the standard deviation to conduct the t-test.

list=[0.00330, 0.0022, 0.0018, 0.0016, 0.001, 0.0013, 0.0011, 0.00, 0.001, 0.0007]

So again, Before I do anything code related,I need to know if more components are required to conduct these t-tests in the manner in which I describe above. (These standard deviations were generated through a bootstrapping process, if it helps anything to know)

But, if I do not need to furnish any further information, I would appreciate any help in generating the code for the t-test.
I have problems with coming up with the exact dollar match of $3345.90 based on the original term of 5.87.  I need help with finding a better formula to get the total price match per the term months. A file that shows the formula I am using is attached.
The Point is      x=0.6160      y=0.8308
Determine coefficients of the equation for a second order polynomial in the format:
I was thinking about magnetism and it seems that both immobile charges are affected.

We have a wire conducting current and we have a positive charged cat.

At our rest frame the cat won't be repulsed from the wire . But in another frame when we consider the electrons (which are the current) immobile then due to length contraction the charge density of both the cat and the nuclei will be increased so a repulsive force will exist.
In forward bias mode there is an energy difference between electrons from n-type doping  and electrons moving from the semiconductor material  because of the difference  band gap .

Where does the remaining energy go?
Well an LED's colour is determined by the energy band of  the semiconductor(GaAs). If the impurities have different  energy band than the semiconductor  where does the remaining energy go?
I would like to ask how current flows through a water doped with NaCl

*First H20 molecules dissolve NaCl. Na+ and Cl- are created .

*When we apply a external voltage source Cl- anions are attracted to the positive electrode(cathode) and Na+ cations to the negative electrode(anode)

*2 Cl- anions are oxidized according to this reaction 2Cl- ->Cl2 + 2e-

*Those 2e- travel through the battery and go the cathode where they meet 2Na+ + 2e- +2H20 -> 2Na + 2OH- +H2

how does current flow after this?

Is current carried with OH- . If yes how and why?
Well i would like to ask this :

If a transistors is on active mode

Diffusion current flows from the emmiter towards the base.

Some electrons combine with holes in the base and then spread towards VB voltage

Most of electrons have no holes to combine so they create the output current

How is it possible those electrons(which are very many)pass as an drift current (Base-Collector junction reverse biased) only as minority charge? I mean there are not enough free electrons in the p-type region(base) to allow all of those electrons to pass
Well i have a question:

Here it is my circuit

The circle with the arrow is an npn transistor

why when i increase the value of R1 and voltage drop  in R2 gets bigger?

well im having this trouble for several days.

where am i wrongThe circle with the arrow is an npn transistor
Python 3 Fundamentals
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Python 3 Fundamentals

This course will teach participants about installing and configuring Python, syntax, importing, statements, types, strings, booleans, files, lists, tuples, comprehensions, functions, and classes.

I have a circuit with a transistor and a light emmiting diode:

My source voltage is 11.6 volts

My transistor is in series with 2 resistors and the light emmiting diode.

The resistors values are 1000 Ohm each.

The base is connected to a 0.7 volt supply.

Voltage drop in resistors is 2.7 volts each.

The voltage drop in the light emmiting diode is 2.7 volts

Why is there a 3.4 V voltage drop between emmiter and collector?Shouldnt it be 0 and the voltage drop in the resistors be (11.6-2.7)/2 volts ?

What am i missing?

Need help with a formulas to calculate:
1. (Cell DM23) Most recent past 6-week run rate of 52 week historical data that excludes zeros and high- low numbers (seasonality/Standard Deviation > X).
2.  (Cell DN24) Return data in Range $BM$22:$DL$3171 in column DN depending on current week written in Cell DM16

(see attached file)
Well i would like some help here:

A semiconductor's resistance is relevant to its impurities . The p-type doped region in an NPN transistor is very thin.So Why many electrons pass through from the emmiter to the base since base resistance is very big?
The demand of IT service is a random variable (X) having the Poisson distribution ΞΌ=3.4. The cost of producing each pizza is 20 and each is sold at selling price of 40.
Suppose 5 pizza are made daily, no pizza is reserved for next day. Find the expected total profit daily.

p(0) x -100 + p(1) x -60 + p(2) x -20 + p(3) x 20 + p(4) x 40 + p(>=5) x 100

My answer = 27.1004. Suggest ans = 27.118.

Do I miss anything ?
I have an index and it is only published quarterly. I want to change it to monthly data.  I did the to the power 1/3 so each month in the quarter has the same return and it produces the same return as the quarter. This causes correlation problems with other indices which has monthly data.

Index 1 (Quarterly Data)
Index 2 (Monthly Data)

Index 1
Quarterly Return 0.48%

Index 2
June -6.71%
July 1.29%
August 2.65%
Which bring this quarterly return to -3.00%.

When I am converting Index 1 to monthly data , i would like to use Index 2 as a guidance.  So, it needs to weighted using the Index 2 data when making Index 1 monthly.

I tried the following.

For June Index 2 x1 = (1+ -6.71%)/(1+ 3%) - 1
For July Index 2 x2 =(1+ 1.29%)/(1+ 3%) - 1
For August Index 3 x3 = (1+ 2.65%)/(1+ 3%) - 1

For June Index 1  y1= (x1/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)
For July Index 1 y2= (x2/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)
For August Index 1  y3= (x3/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)

Then when I compound (1+y1)(1*y2)(1*y3) - 1 = 0.48% So it worked for this quarter.

It works great for some quarters but it doesn't work for some quarters. In some quarters, when I compound y1 y2 y3, i get a number very different from the actual quarterly data for Index 1.  Please see the attached file for the excel file. It has the calculations.
Hi I have a problem, I'm trying to solve for x,

Is there a way to calculate percentile rank using a conditional statement. For example, PERCENTRANK.EXC of column Ratio if Rating value is AAA. Example is attached.


I am unable to understand how we can derive: (S,K and cap are positive integers)

3*( max(S-K,0) – max(S – (K+Cap/3),0))


3* min(max((S – K,0), Cap/3)

From plugging values in 3* min(max((S – K,0), Cap/3) , I can see that it is equivalent. But how do i think about this?

Water molecules can be joined by hydrogen bounds. Should be these clusters calculated as one particle? Is there any theory that can estimate the numbers of all particles (moles) per one kilogram of pure water? Is it possible to calculate also the distributions of the water molecules through these clusters? E.g. number (moles) of clusters composed with two molecules of water.
Microsoft Azure 2017
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Microsoft Azure 2017

Azure has a changed a lot since it was originally introduce by adding new services and features. Do you know everything you need to about Azure? This course will teach you about the Azure App Service, monitoring and application insights, DevOps, and Team Services.

I have a set of points and if I draw them on a paper, I have a diagram like the image in attached file.
I want to find any almost horizontal curve/line in the scattered points, something like another image in the attached files, the image with red diagram.
the result will be like below image:

In fact what I want as output is an array of points that are on the line/curve, or the equation which gives me the y component of the point if I set the x value.

I searched for a Java/Android library or code that does the job but didn't find any. I would appreciate if you let me know about the exact mathematical process or any Java/Android library or class that does the job.

Thanks in advance.
Dear experts,

The below url shows the compound interest calculations - discrete and continuous.

In the video between time lines 6.45 minutes - 7.05 minutes, it shows log 2/0.05 = 11.55 yrs

If log 2 to the base 10 gives 0.3010. Then 0.3010/.06 = c5.016. How is the number 11.55 arrived?

Is it considering log 2 to the base 'e'?

then in which cases do we calculate log use base 'e'?

Thank you

Kindly help.
Hi to all,

I use findpeaks function in my code to calculate the four maximum values of a fft function.

I use it in this way:

[maxpeaks, idx] = findpeaks(10*log10(psdx),'MinPeakDistance',195,'NPeaks',4,'MinPeakHeight', -Inf, 'SortStr','descend')

Open in new window

The problem is that I need to run the code in a Matlab version which doesn't have the Signal Processing Toolbox. Is there any solution to write a similar function without the need of the SP Toolbox?

Thank you!
Hello! I am trying to figure out (am I am completely new to Livecycle) how to track an employees time they spent traveling whether it be in one day or for overseas folks multiple days, and either find the time duration or adding the estimated time it takes for each segment of their trip in order to calculate the time our of their normal work hours they are eligible for time compensation. I cannot decide if its easier to do a duration between two times or do like the previous form in excel , and calculate with decimals. After the time duration is calculated, they will enter in either decimals or mins, the time it takes to get from their home to work and it will be subtracted from the total hours they spent traveling. I have been searching for formulas to do this but I don't have an experience with javaspript or formcalc. When someone does post a formula I have no idea how to implement it into livecycle. Thanks!
I would like to perform fractal analysis on a financial series (stock exchange index). What shall I use (prices or log returns) for calculating fractal dimension, Hurst Exponent, for performing R/S Analysis and for predictions? Are there R functions that calculate all of these immediately? Are there any things I need to take care of when analyzing the index? Thank you in advance!
At the time of Solving the angle dependence with time for a simple pendulum without taking approximation i got a 2nd degree Differential equation After integrating for one time i got a constant and took It as m and end up with another Integration and lost My Hope over It.
Integral of one over Square root of (m+cosx) last Hope that one may say how to solve this πŸ˜–πŸ˜–