## An error message from a backtracking procedure...

I'm experimenting with a backtracking procedure to solve the subset-sum problem: given a list L of integers, and an integer N not in L, to see if elements of L can be found which sum to N.  Basically the procedure works recursively, adding elements to the current list until either the sum equals N, in which case we stop with a solution, or the sum exceeds N, in which case we go back one level:

## not show my plot...

hi

i use under code for plot

but only vertex has been show

help me

with(plots);

with(stats);

f1:=y-

## Maple 11 Loglog Plot...

The Maple11 loglog plot does a poor job in scaling and axis.  The plot works, but, compared to something like the Scilab bode plot, the scaling and axis presentation is poor.

Someone on another forum mentioned an application that improves this.  I searched and found nothing.

Is there an application that improves this?

tomdean

## Dsolve Stop condition...

I want to use the STOP_COND option in dsolve when z(t)=0 and t>0.

This is because at t=0 z(t)=0, and I want it to continue until z(t) returns to 0 again.

## Thomas Exercise 5.6.39 won't integrate on Maple...

Thomas Exercise 5.6.39 won't integrate on Maple. I tried it using int, simplify, eval, etc. But the answer won't show. The exercise is shown below.

## Suppressing scientific "e" notation in Maple on th...

Hi everyone.

I have a very particular situation here: I'm running a series of programs that grab string output from command line Maple as plaintext. For this reason, I don't have the normal Numerical Format dropdowns, etc., available to me for this issue.

## Assumption ignored while solving integral...

Hi folks,

I'm trying to get the fundamental solution of

-diff(A,t)+a(x,t)*laplacian(A,[x,y,z])=0;

I had some troubles entering the code here, so I uploaded the maple commands here: http://pastebin.com/m2765fda0

when I call eval(phi(x,t,xi,tau));  to calculate the fundamental solution, I always get the error 'Error, (in w) numerical exception: division by 0'.

Shouldn't my assumptions avoid this error?

Manuel

## How to fix the ratio of height to width for a figu...

Dear all,

How can I fix the ratio of height to width as 0.618 when plotting figures ? The command scale=constrained seems not appropriate   If  someone  knows how to realize it , please tell me ASAP. Thank you very much !

Kindly regards,

Yours

huang

## Integral displays infinity (mistake ?)...

f := sec(x)^2;
Int(f, x = 0 .. 5*Pi*(1/4)) = int(f, x = 0 .. 5*Pi*(1/4))

I enter the above in Mape 12 Student Edition, and the answer is infinity, but it's obviously 1.

How can I get Maple to display the obvious ?

## bifurcation...

How could I plot bifurcation for a nonlinear system using maple? For example I have the following nonlin. syst: x'=a*b*((x^2+c^2)/(x^2+1))-d*x y'=a*e*((y^3+f^3)/(x^3+1)*(g*x+1)-y for a, b c, d, e, f,g be given ; I want to get bifurcation by some parameter, e for instance.

## Convert string to integer...

I am using the readline command to read in values from a text file, but they are coming in as strings. How can I convert these to integers?

## Export multiple jpg Files...

I am using Maple 10 and i want to export as "jpg" files multiple columngraphs. These columngraphs are generated from:

>for k  from 1 to 100 by  5 do

ColumnGraph(points[k],color=blue,axes=BOXED,thickness=2,print(t=k),view=[0..26,0..0.1]);

od:

Then i use the command :

>for k  from 1 to 100 by  5 do

plotsetup(jpeg,plotoutput=`k.jpg`);

od;

but exports only one file called "k.jpg" .

## Simplifying through codegen/optimize/tryhard

by: Maple

In a concurrent thread I posted the following simplification procedure

```  Tryhard:= proc(expr)
global E_in_Tryhard;
subs(pow= `^`,
codegen[optimize](subs(E_in_Tryhard= expr, ()-> E_in_Tryhard), tryhard))()
end proc;
```

and now put into an extra blog post, as it might be helpful for others. Note, that this does not work on all constructs in Maple and certainly the package is a bit dated.