MartinUser

20 Reputation

3 Badges

10 years, 306 days

MaplePrimes Activity


These are questions asked by MartinUser

Maple 16 code

 

N1 := FileTools[Text][CountLines](g)

I encounter an error message

in FileTools:-Text:-CountLines) permission denied

What  went wrong ?  This never happened before

I  re install  Maple 16, the same error persists.

 

Please help

Martin
 

expand( (a+b)^n)

 

convert((a+b)^n,Sum) 

 

none  expands in  binomial  form.  Is there any way for Maple to generate  binomial  expansion of (a+b)^n  without

 

entering  manually.

 

martin

intergration

f:=Intat(1.0000000000000000000*(1.7969454312181156991*_f^1.2+1.80)^1.2/sqrt(-1.4974545260150964159*(8.9847271560905784954*_f^3+14.640368911168931285*_f^2+30.220202497712627297)^1.2), _f = 0);

 

I tried to use  value(f);  eval(f); simplify(f); expand(f), but non provide an answer, but return an integral unevaluated.

 

Is there a command to produce a  numerical result ?

I  get  this  from  pdsolve as a  "solution"

 

p[42] := -Pi+.2+3.0*x+3.2*t+2*Intat(2.25*_f/sqrt(-1.5*_f*(-1.6+4.0500*_f^2+3.7125*_f)), _f = 0)

 

it does not eval to anything, what is this ?

I encounter "insufficient  initial/boundary value" error message,  do know how to proceed from there, search with "insufficient initial value" gets no result. Any help will be appreciated.

 

 

> restart; alias(r = r(t), f = f(t)); with(plots);
r, f
> DE := diff(r, t) = 2*r+alpha*r*f, diff(f, t) = -f+alpha*r*f;
d d
--- r = 2 r + alpha r f, --- f = -f + alpha r f
dt dt
> NULL;
> params := alpha = .3;
alpha = 0.3
> initv := r(0) = 101, f(0) = 2;
> NULL;
>
> dvars := [r, t];
> chaodisplay := proc (chartname) EQ := [op(subs(params, [DE])), initv]; EQ1 := dsolve(EQ, numeric); odeplot(EQ1, dvars, t = 0 .. 300, axes = frame, numpoints = 50000, color = green, orientation = [-30, 100], title = chartname) end proc;
Warning, `EQ` is implicitly declared local to procedure `chaodisplay`
Warning, `EQ1` is implicitly declared local to procedure `chaodisplay`
>
> chaodisplay("Rabbit and Fox");
Error, (in dsolve/numeric/type_check) insufficient initial/boundary value information for procedure defined problem
>

Page 1 of 1