@J4James Where did you get the "exact" solution? It seems wrong. You can check that it doesn't satisfy the original equations like this:

F1test:= unapply(Exact, eta):
eval(eq1, F1= F1test):
plot(lhs(%), eta= 0..n);

It should be identically 0, modulo some rounding errors. Note that I am not comparing Exact against the computed numeric solution; I am comparing against the original differential equation.

Please ask any further questions in a separate thread. You're lucky that I saw your Reply, because it is difficult to find Replies to old Answers.

I think that the Asker wants single-precison hardware floats, which can be accessed with datatype= float[4].

I think that the Asker wants single-precison hardware floats, which can be accessed with datatype= float[4].

There is no file attached to your post.

To change the default input to the way I have it, go through the following menu sequence: Tools => Options => Display => Input Display => Maple Notation => Apply Globally.

There must be a difference in the floating-point evaluation in Maple 15 or a different processor that you may be using. I cannot reproduce your errors. The evalf is necessary to handle cases where the fibonacci has more than Digits digits. Without it, the ceil and round will return unevaluated for x  > > 10^Digits.

Please try testing with one more digit of precision: Change evalf[2+ilog10(x)] to evalf[3+ilog10(x)].

To change the default input to the way I have it, go through the following menu sequence: Tools => Options => Display => Input Display => Maple Notation => Apply Globally.

There must be a difference in the floating-point evaluation in Maple 15 or a different processor that you may be using. I cannot reproduce your errors. The evalf is necessary to handle cases where the fibonacci has more than Digits digits. Without it, the ceil and round will return unevaluated for x  > > 10^Digits.

Please try testing with one more digit of precision: Change evalf[2+ilog10(x)] to evalf[3+ilog10(x)].

@brian bovril 

The command for that is

map(`>`, {a,b,c,d}, 0);

Note that the quotes are back quotes, not aposthropes. What the above means is

1. `>` is an operator that takes two arguments,
2. the first argument is taken iteratively from {a,b,c,d},
3. the second argument is always 0.

Another command that does the same thing is

{seq(x>0, x= {a,b,c,d})};

@brian bovril 

The command for that is

map(`>`, {a,b,c,d}, 0);

Note that the quotes are back quotes, not aposthropes. What the above means is

1. `>` is an operator that takes two arguments,
2. the first argument is taken iteratively from {a,b,c,d},
3. the second argument is always 0.

Another command that does the same thing is

{seq(x>0, x= {a,b,c,d})};

@ecterrab I am using Maple 17.01, Standard GUI, 64-bit, Windows 8. The given macro command fixes the problem for me.

@Kitonum This last piece of code is very impressive.

@Kitonum This last piece of code is very impressive.

@ecrkae You need to give values for A, c_3k, etc.

@ecrkae You need to give values for A, c_3k, etc.

You are assuming that the letters represent distinct digits. That may be the default assumption in such problems; I don't know.

It is immediately obvious that C=9, K=1, and R is even. Applying essentially your technique, I get 94 solutions in about a half second.

restart: st:= time():
S:={$0..9}:  L:= table():  C:= 9:  K:= 1:
for N in S do
for R in {0,2,4,6,8} do
for P in S do
for H in S do
for M in S do
for E in S do
     a:=C*10^3+N*10^2+R*10+P:
     b:=C*10^2+P*10+P:  
     c:=K*10^4+H*10^3+M*10^2+E*10+R:
     if a + b = c  then  L[CNRP=a, CPP=b, KHMER=c]:= [][]  fi:
od: od: od: od: od: od:
time()-st;
nops([indices(L)]);
                             0.547
                               94

You are assuming that the letters represent distinct digits. That may be the default assumption in such problems; I don't know.

It is immediately obvious that C=9, K=1, and R is even. Applying essentially your technique, I get 94 solutions in about a half second.

restart: st:= time():
S:={$0..9}:  L:= table():  C:= 9:  K:= 1:
for N in S do
for R in {0,2,4,6,8} do
for P in S do
for H in S do
for M in S do
for E in S do
     a:=C*10^3+N*10^2+R*10+P:
     b:=C*10^2+P*10+P:  
     c:=K*10^4+H*10^3+M*10^2+E*10+R:
     if a + b = c  then  L[CNRP=a, CPP=b, KHMER=c]:= [][]  fi:
od: od: od: od: od: od:
time()-st;
nops([indices(L)]);
                             0.547
                               94