maple2015

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These are questions asked by maple2015

Hi

Dear friends

I use the command "dsolve(`union`(deq, initial), numeric, method = lsode)" for solving a fourth order ODE.

But for some numerical values of the parameters the bellow error is occurred:

" an excessive amount of work (greater than mxstep) was done ".

I have three questions:

1- how can I increase the mxstep from default amount (i.e. 500) to a greater value?

2- how can I ensure that the absolute error is less than 10E-6?

3- when I use lsode which way of numerical solution is applied (Euler,midpoint, rk3, rk4, rkf, heun, ... )?

 

Thanks a lot for your help

Hi

Please find the attached file

The command PolynomialInterpolation doesn't work, I will be appreciate if you can help me

Thanks

 

Question.mw

The scale of vertical axis is logarithmic and function in each interval must be linear. When I use the command " mode=log " the shape of lines are deformed into curves, however when I use the command " curve ", the shape of lines remains straight. I can use right-click for changing mode to logarithmic scale but is it possible to use label font for vertical axis as well as size, resolution and other options in the command "curve" ?

Thanks alot

 

 

restart; with(plottools):

SN := curve([[3, (4.566256-4.544647)/(4.544647)], [4, (4.544933-4.544647)/(4.544647)], [5, (4.544653-4.544647)/(4.544647)], [6, (4.544649-4.544647)/(4.544647)], [7, 0]]): PLOT(SN);

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for m to 5 do

x[m] := m+2 end do:

y[1, 1] := (4.566256-4.544647)/(4.544647):y[2, 1] := (4.544933-4.544647)/(4.544647): y[3, 1] := (4.544653-4.544647)/(4.544647): y[4, 1] := (4.544649-4.544647)/(4.544647): y[5, 1] := 0:

for j to 1 do for i to 4 do

L[i, j] := (y[i+1, j]-y[i, j])*(x-x[i])+y[i, j] end do:

PW[j] := piecewise(`and`(x >= x[1], x < x[2]), L[1, 1], `and`(x >= x[2], x < x[3]), L[2, 1], `and`(x >= x[3], x < x[4]), L[3, 1], `and`(x >= x[4], x < x[5]), L[4, 1]) end do:

plot(PW[1], x = x[1] .. x[5], color = black, axes = framed, font = [Times, 13], size = [650, 550], resolution = 1200, legendstyle = [location = top], legend = ['gamma' = -.4], linestyle = solid, thickness = 2, labels = [Number*of*Basis, '(P-P[min])/P[min]'], labelfont = [Times, 13], axis[2] = [mode = log]);

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Hi

When I run a maple file it uses 25% of CPU.

When I run 2 files, the half of CPU is used.

How can I change the preferences for using most of CPU

Hi

Please help me to solve EQ in attached file.

I need amount of P.

 

 

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