I want to write a procedure P such that the input of P is a positive integer number n and the output of P is a random permutation of the numbers {1,2,..,n}. 

I know that there is a command in Maple 2017 such that the command produces the mentioned request (random permutation in the combinatoric package), but I should work with Maple 15 and there is no the random permutation command in Maple 15. 

One of the solutions that I am used is based on the random number and check that if the produced numbers are pairwise distinct or not. The problem of this method  is that for n>128, it takes too time to generate a random permutation of the length n.

Thanks for any suggestions. 

I'm trying to better understand the Black and Scholes model; which is a scalar function on (positive reals)^5.
a maplesoft worksheet defines it as

BS_Price=exp(-r*T)*(-(1/2)*erf((1/4)*sqrt(2)*(sigma^2*T-2*r*T+2*ln(K)-2*ln(S[0]))/(sigma*sqrt(T)))+1/2)

I am trying to understand the parameter vectors (r ,T,K,S[0],sigma) that give the same values of BS_Price - and particularly whether these form curves, closed curves, surfaces or similar.

Right now, I am not sure how to procede.

EDIT
I've just put together  a procedure that evaluates BS at points in R^5 - and i think i can move forward by using the curry or rcurry functions to get a 5d tensor of the values of BS, that i can start to look for patterns within.

BS_Price := proc (InterestRate, StockPrice, StrikePrice, Duration, Volatility) evalf(subs([r = InterestRate, S[0] = StockPrice, K = StrikePrice, T = Duration, sigma = Volatility], exp(-r*T)*(-(1/2)*erf((1/4)*sqrt(2)*(sigma^2*T-2*r*T+2*ln(K)-2*ln(S[0]))/(sigma*sqrt(T)))+1/2))) end proc

could anyone give me advice on doing this?
 

The animation in this worksheet seems realistic but I wonder if the physics which is implemented is correct since there is no explicit mention of rotational energy.

ThrowBola.mw

Hellow, help required to remove the errors

 How to  obtain the pressure drop i am unable to get the output. I am uploading the file  and the equations

help_dp.mw

Hi, I’m new to maple and I’m not very good with these things, but could someone tell me if there’s a way to calculate a^b with large numbers?

I’ve tried to do it but it just says evaluating in the bottom left corner but doesn’t actually do anything. This is an example with two of the large numbers i have to use(if this helps):

815427339135043^5579408896058

Thank you in advance for any help.

Good day!

I wish to represent the flow across a network from a set of sources to a number of destinations or sinks.

In the simple example attached, there are 4 sources and 10 possible sinks. The flow from source to sink is given by the matrix, A, and each element is a binary entry; 1 for active and 0, otherwise. I would like to assign labels to each source (A,B,C,D) and sink (1,2,3,..., 9,10) and this feature will be most convenient for large matrices.The idea is to have these labels shown on the directed graph so that it is easy to see the flow configurations at a glance.

Does anyone know how this can be done?

Thanks in advance.

MaplePrimes_network_labels.mw

Help required to get the derire output  for the differential equation . I am attacing the codes and the sample output.

restart:
with(DETools):
a1:=m^2*((1-N)/(2-N))*(r/2)*Dp:
a2:=((1-N)*m^2/(2-N))*(((Nb-Nt)/64)*(r^5/6-h^2*r/2)-(B[r]/4)*(r^3/4-h^2*r/2)*(Nt/Nb)):
a3:=a1-a2:
a4:=r^2*a3:
DE1:=r^2*diff(v(r),r,r)+r*diff(v(r),r)-(m^2*r^2+1)*v(r)=a4:
b1:=dsolve(DE1,v(r)):

Hello

Could you please help me to solve the following problem

I want to catch the optimized values for df, tf, hw, and tw using considered constraint.

Thank you very much.

with(plots); R := 5; alpha := (1/9)*Pi; beta := (1/3)*Pi; n := 100; dt := 2*Pi/n; C1 := plot([R*cos(t), R*sin(t), t = 0 .. 2*Pi], color = blue); O := [0, 0]; M := [R*cos(beta), R*sin(beta)]; A := [R*cos(alpha), R*sin(alpha)]; B := [R*cos(alpha+Pi), R*sin(alpha+Pi)]; AB := plot([A, B]); OM := plot([O, M]); P := [R*cos(t0*dt), R*sin(t0*dt)]; Q := [R*cos(dt*t0+Pi), R*sin(dt*t0+Pi)]; diamob := seq(plot([P, Q], color = green), t0 = 0 .. n); MP := plot([M, P]); MQ := plot([M, Q]); tp := textplot([[A[1]+.3, A[2], "A"], [B[1]-.3, B[2], "B"], [M[1]+.3, M[2]+.3, "M"]]); display({AB, C1, OM, tp, display(diamob, MP, MQ, insequence = true)}, scaling = constrained):
I wish animate MPand MQ.

Is there a way to take the laplacian of 1/r and get the "physics" answer of -4*pi*delta(\vec{r})?

Dear Community,

I'm trying to import a simple Excel (xlsx) file into my Maple worksheet.

1st problem: Maple reads it only, if I put it into my root directory. As soon as I try to read it from the directory I'm working in, and provide full file name (Path + file name)  it fails. Why?

2nd problem: The real surprise comes, when I manage to import it. Its a 150 x 2 matrix, but as soon as I try to retrieve a value, I get an error message "Error, bad index into Matrix". Why is this? Should be very simple. Files attached.

Tx in advance

best regards

Andras

ImportTest.mw, 

RC_Rate_Schedule.xlsx

For a statistical course I will give next year, I would like to demonstrate the calculation of tetrachoric and polychoric correlations. Furthermore, it would be nice to show the students how the expectation-maximization algorithm works.

Has anyone already programmed this in Maple?

best regards,

Harry

Hello,

I´a currently making a school assigment, but i can´t get maple plots to combine the graphs i plot, when i plot multiple plots. (see picture) (the code is in the bottom of the question)

I want to plot all three "roots" of the polynom I called 'H[i]' for different values of 'V', in the interval k=0.0..1.0, all in the same plot.

How can I do it, both for real and imaginary parts of H[i]?

Thanks for your help.

file1.mw

with(plots):R := 5; alpha := (1/9)*Pi;
C1 := plot([R*cos(t), R*sin(t), t = 0 .. 2*Pi], color = blue);
A := [R*cos(alpha), R*sin(alpha)]; B := [R*cos(alpha+Pi), R*sin(alpha+Pi)]; AB := plot([A, B], scaling = constrained);
display({AB, C1}, scaling = constrained);# bad drawing