The code generting module C writes  result to screen. How to I get it to file?

Dear Users!

I hope everyone is fine here. I have the following functions:

f := cos(t)*sin(x)-sin(x)+(1/2)*sin(x)*t^2-(1/24)*sin(x)*t^4

I want to plot the contour plots with legends like given as (this is the countor plot just for reference):

I want the same coloring to fill the contour plots. Kindly help me to resolve my problem. Thanks in advances

(I would prefer a solution for Maple 2015, but answers relative to newer versions are welcome)

Is there a simple way to force the result -y(1) + y(2) without using one of these two tricks?

# how can I get the expression of
int(diff(y(x), x), x=1..2);
                      / d                  \
                   int|--- y(x), x = 1 .. 2|
                      \ dx                 /

# Trick 1
int(diff(y(x), x), x);
eval(%, x=2)-eval(%, x=1)
                              y(x)
                          -y(1) + y(2)

# Trick 2
J := Int(diff(y(x), x), x = 1..2): 
value(IntegrationTools:-Parts(J, 1));
                          -y(1) + y(2)

TIA

I found this option in an API command ?MapleSim,LinkModel,Simulate:

    scalemethod : one of the following: "none", "minimum", "maximum", "geometric"
    Method of variable scaling applied to the system.

I did not find anything about scaling in Maples help system.

What exactly does the scaling do?

According to the help page for optimize

"The optimize function makes use of Maple's option remember facility to identify common subexpressions in linear time and space. This means, however, that only those subexpressions which Maple has simplified to be identical are found. For example, the expression 
                            "x + y"

 is not recognized as being common to  
                          "x + y + z"

. That is, optimize performs mainly "syntactic" optimizations."

Is there a way to more efficiently calculate a set of expressions that have common factors as in the example above?

 In the memory leak problem with my DStarLepNu simulation program, I did find one cause in that due to normalization errors the accept/reject algorithm in ‘PickAngles’ was executed too many times. This should have just made angle generation inefficient but occasionally, but not always produced very big memory bumps when a large number of trials were needed to pick angles. It’s not clear why these bumps occurred as the code being executed is always the same and is simple.

Fixing this did however not prevent memory crashes or even reduce them much.

I have since turned off accept/rej and calls to ‘arccos’ and more modest spikes remain and crashes still occur!

I don’t understand how Maple memory management works. My B-meson decay prov ‘bDecay’ usually gives  still shows occasional spikes and and there’s a weird correlation between the first (B1) and second (B2) call:

DStar3DKinRecoLoopDebugCombo200EventsExportRun2.mw

çMemory added by ‘bDecay’ proc on 1^st call vs 2^nd call in the B1-B2 event loop..

èWhat with the slope and difference in width?

can you help to solve and plot the followng delay ODE

ode:=diff(y(x),x)=1-2*y(x/2)^2;                                                                                                                                                            ics := y(0) = 2    ;            y3:= dsolve({ics, ode},numeric, delaymax = 1.7);  YY5:=odeplot(y3,x=0..10); 

I found the option in this statement

dsn := dsolve(dsys, numeric, differential = true, projection = false, maxfun = 0)

in help("examples/numeric_DAE")

I give up searching because

• the word "differential" occurs so often in dsolve help pages that advanced search does of not filter help topics effectively
• the option does not seem to be a dsolve[numeric] or rk45 specific option (at least I cannot find anything on the pages)

What does the option do?
How could I have searched better?

How do I set the axis range in a Maple scatter plot. It's not evident to me from the Help.

Please help me how to impliment to solve this problem 

Download dust_practice_code.mw

dust_paper.pdf

Dear Users!

I hope everyone is fine. I want to plot the following sequence in 3d for t=0..1 and x=-pi..pi;

[0., 0.4995839572e-1*sin(x), 0.9966865249e-1*sin(x), .1488899476*sin(x), .1973955598*sin(x), .2449786631*sin(x), .2914567945*sin(x), .3366748194*sin(x), .3805063771*sin(x), .4228539261*sin(x), .4636476090*sin(x), .5028432109*sin(x), .5404195003*sin(x), .5763752206*sin(x), .6107259644*sin(x), .6435011088*sin(x), .6747409422*sin(x), .7044940642*sin(x), .7328151018*sin(x), .7597627549*sin(x), .7853981634*sin(x)];

In the sequence first entry (0) for t=0, second (0.4995839572e-1*sin(x)) for t=0.05, third (0.9966865249e-1*sin(x)) for t= 0.1 and so on the last entry (.7853981634*sin(x)) for t=1. In addition, how do I plot if the number of points exceeds in the sequence for example 100 or 1000 points, but the difference between two consecutive values for t is the same here the difference is Delta*t=0.05.

As my jobs are still crashing with memory leak, I'd like to write results out to files and read them back to add them together.

I see something called 'Export' and something called 'Import'. It didn't work for me. Does the file have to already exist? An example would be nic

I want to plot this function in cylindrical coordinates in a way that it is clear where the function is greater than zero and where it is less that zero. I was wondering what would be the best way to do it. It has two arbritary constants. Usually when I have only one constant, I animate the plot for different values of that constant. But I am not sure what to do for this case.

-2*M^2*sin(theta)^2 - 2*k*r^2

eq1 := diff(f(x), x, x, x)+(1/2)*x*cos(alpha)*(diff(f(x), x, x))+(1/2)*sin(alpha)*f(x)*(diff(f(x), x, x))+G[r]*theta(x)+G[m]*phi(x) = 0;

eq2 := diff(theta(x), x, x)+(1/2)*Pr*cos(alpha)*x*(diff(theta(x), x))+sin(alpha)*f(x)*(diff(theta(x), x))+N[b]*(diff(theta(x), x))*(diff(phi(x), x))+N[t]*(diff(theta(x), x))^2 = 0;

eq3 := diff(phi(x), x, x)+(1/2)*Le*cos(alpha)*x*(diff(phi(x), x))+sin(alpha)*f(x)*(diff(phi(x), x))+N[t]*(diff(theta(x), x, x))/N[b] = 0;

ics := f(0) = 0, (D(f))(0) = gamma*((D@@2)(f))(0), theta(0) = 1+tau*(D(theta))(0), phi(0) = 1;

bcs := (D(f))(infty) = 0, theta(infty) = 0, phi(infty) = 0;

Parameters := G[r] = 5, G[m] = 3, Pr = 7, N[b] = .1, N[t] = .1, Le = 1, gamma = .2, tau = .1, alpha = 30*degree;

Hi Everyone, 

I have a numeric integral which I hope to evaluate (ideally over a infinite domain) that for some reason is giving me difficulty and I cannot seem to find a work around. I want to use method = _d01amc in the integral as a means to speed up the process - I am motivating this by the answer i recieved from @acer in https://www.mapleprimes.com/questions/236772-Any-Ideas-On-How-To-Speed-Upimprove - however I keep recieving an error indicating overflow. 

This seems rather strange to me due to the fact that if I omit a method and just let Maple do its own thing it will eventually spit out an answer albeit slower then I would prefer for the procedure I am going to eventually impliment. 

My integrand and attempts/confusion can be seen in the attached worksheet. 

Any thoughts appreciated. 

OverflowError.mw