Hello everybody, 

I used Maple to reach a function in terms of a few parameters. The issue that I'm facing is that when I copy and paste that equation to excel(after transforming that same equation to 1D math) for evaluating it's value with the real values for the parameters, the result is not the same as the one calculated by Maple 2016 with the exact same parameters. I've inserted the file with this question for further information. One of the parameters (F15) is the cell used in excel.

equation.mw

Download equation.mw

Any help regarding this problem is very much appreciated.

I have tried

assume(n >= 0, n::integer);

But still,

simplify(exp(-n*ln(2*Pi)))

does nothing.

I want to convert it to (2*Pi)^(-n).

Hi,

I am doing Principal Component Analysis (PCA) and I think the Biplot procedure could be improved.

When you use PCA is common to look what happens in other planes than the plane defined by the first two eigenvectors.
Unfortunately Biplot deals only with 2D projections onto this first plane and with 3D projections onto the space spanend but the first three eigenvectors.

I modified slightly the original Biplot procedure for it to handle different 2D and 3D projections planes.
The code is given in the attached mw file (original commands are written red over yellow and the new ones yellof over red).

I'm not at all certain mapleprimes/questions is the best place to post ???


Biplot.mw

Hi,

This sequence of commands works perfectly well

     plotsetup(jpeg, plotoutput=SomeJpegFile);
     plot(x, x=0..1);
     plotsetup(default);


Why this one doesn't create the file SomeJpegFile ?

f := proc()
     plotsetup(jpeg, plotoutput=SomeJpegFile);
     plot(x, x=0..1);
     plotsetup(default);
end proc;

f();


Thanks in advance

Maple gives the integral's face instead of giving a number as the numerical integration, no matter what command for the numerical integration I use. Does any one know what the problem is?

T2start := -5.036645000*10^9*(x[5]^2+.2725890432*x[5]+.3732640349)*x[5]/(5.036645000*10^9*x[5]^2+1.27004241*10^8*x[5]+5.3714241*10^7); 
T2end := -5.036645000*10^9*(x[5]^2+.2871403962*x[5]+.3945934083)*x[5]/(5.036645000*10^9*x[5]^2+1.27004241*10^8*x[5]+5.3714241*10^7);
J := (25183225000000*x[5]^4+(-100732900000000*T[2]+73827142410000)*x[5]^3+(-112645777230000*T[2]+662242877289)*x[5]^2-2398770574578*T[2]*x[5]-393671672289*T[2])/(10000000*x[5]^2+14658000*x[5]);
int(abs(J), [T[2] = T2start .. T2end, x[5] = 0 .. infinity], numeric);

I also used the following.

evalf(Int(abs(J), [T[2] = T2start .. T2end, x[5] = 0 .. infinity]));

The result was same.

Or when I use

evalf(Int(abs(J), [T[2] = T2start .. T2end, x[5] = 0 .. infinity], method = _MonteCarlo));

It gives an error saying:

Error, (in evalf/int) invalid arguments

Wus poppin Jimbos

My function is as follows:

f(x)=(10000/1+30762*0.478^x)+5

I can then type 

maximize(f'(x))

And I get the result which is approximately 1845.361367

I then assign at a name e.g. "M"

I then try and execute the command (where I isolate the expression for x)

f'(x)=M

I get the result

 
              x = 14.00001597 - 0.00005369289477 I

Which is super annoying to look at..

Is there any way that I can remove the - 0.00005369289477 I part? And just get the answer (which should be 14)

I have no problem executing 

diff(f(x), x) = 1845.361366;
 = 
                             "(->)"

                        x = 13.99997555

However 1845.361367 once again gives me x = 14.00001597 - 0.00005369289477 I

Any help is appreciated <3

Is it a complete set ? How to search matrix?

When I tried to execute one of my opened worksheets, the "execute the entire worksheet button" became unactive for the others. I am pretty sure there was an option to execute multiple worksheets in Maple 14. Did the developers remove that in newer versions?

u:=(x,t)->Sum(sin(r*Pi*x/20)*(4/(r^2*Pi^2))*sin(r*pi/2)*cos(r*Pi*t/20),r=1...1000);

plot3d(u(x,t),x=0...10,t=0...1);

When I want to draw the graph, it gives a straight line. But this is a wave equation

I am trying to calculate log[1/3](x)-log[sqrt(3)](x^2)+log[x](9) with log[3](x) = a.
I tried:

restart;
sol := solve(log[3](x) = a, x);
f :=x->log[1/3](x)-log[sqrt(3)](x^2)+log[x](9) ;
simplify(f(sol))

I don't get the answer (2-5a^2)/a.

How can I get that answer?

hi

i want to solve a example in this picture but i get error. 

thanks

1.mw

example

Hey, this is not the I've had this encounter. I want to open this saved document but when I open it and Maple starts up it just hits me with "A problem was encountered while opening the workbook. Database is not opened". How can I get to open it properly and see my math notes?

How can this be prevented?

Any help?

Christian

Hi.

When I try to solve the equation 15-1/100M=5+1/600M. The result in maple is 7/6000. But the “real” result according to other calculating programs is 6000/7. Is there a setting that is causing this to happen?

Let us consider

sol1 := dsolve({diff(y(x), x) = solve((1/2)*(diff(y(x), x))^2 = (1-ln(y(x)^2))*y(x)^2, diff(y(x), x))[1], 
y(0) = 1}, numeric);
sol1 := proc(x_rkf45) ... end proc

The problem under consideration has the symbolic solution:

sol2 := dsolve({diff(y(x), x) = solve((1/2)*(diff(y(x), x))^2 = (1-ln(y(x)^2))*y(x)^2, diff(y(x), x))[1], 
y(0) = 1});

sol2 := y(x) = exp(x*sqrt(2)-x^2)

Let us compare the plots of sol1 and sol2 (which should coincide):

A := plots:-odeplot(sol1, x = 0 .. 1, color = navy, style = point):
B := plot(rhs(sol2), x = 0 .. 1, color = red):
plots:-display([A, B]);

The plots differ after approximately 0.707. Bug_in_dsolve_numeric.mw

Edit. The title and one of the tags.

The Fourier series of waveforms with discontinuties experiences an overshoot near the discontinuity known as the "Gibbs phenomenon".  There is quite a bit of literature showing that the overshoot for a rectangle function is ~ 1.089.  What about other functions such as (1-x) or a decaying exponential for x positive?  Is there any reason to expect the overshoot ratio to be identical to the rectangle function?  I do know for a fact that the behavior of the overshoot is different for the triangle function (1-x) than for the rectangle function.  For low harmonics there is an undershoot for the triangle function case, but this is not the case for the rectangle function.  The overshoot occurs for the triangle function after a sufficient number of terms are included in the Fourier series.  The same is true for the decaying exponential.  This is illustrated in my worksheet linked below.

GIBBS_effect.mw

Does anyone know of MAPLE code that computes the theoretical overshoot if there is an infinite number of terms in the series for different waveforms or functions?