## 20 Reputation

0 years, 349 days

## symbolic solution...

Playing around a bit.....

If the entire problem is made symbolic with no numeric values, maple solves it into a huge equation.

But, if in the next step, this huge equation is used with all the numeric constants specified, this huge expression hangs. But after using Digits:=24 and ystart:=2000, the huge expression will look different and  the result becomes correct.

It seems impossible to make it entirely symbolic without specifying ystart. Maple gets overwhelmed.Just fascinating to test the limits.

```y2ove := y -> ap + bp*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na) + cp*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na)^2 + dp*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na)^3 + ep*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na)^4;
y2anom := x -> int(y2ove(y), y = ystart .. x)/tc;
y2anom(x);```

## Thanks...

Thank you very much !  This is awesome

## symbolic solution...

A symbolic solution also suffers from the same problem and returns huge results  ( 10 ^ 11)

Is this also a result of "premature evaluation" ?  Is there a workaround  to get the correct solution ?

## Yeeees !...

I must admit that I don't understand this, but it works !!!!

plot(ta, 2000.0 .. 2050.0)

Thank you !!!!!

## There is something more.........

Thank you very much.  I agree tpn()  undefined...but when corrected -  plot still fails,

To do something radical, I have now replaced all the functions with one single one .   y2ove(y):= a long expression

It returns the right values  y2ove(2000)  -> 12.8     y2ove(2030) -> 58.2

Integrating this function defines a new function

This also returns correct values

y2anom(2000) -> 0     y2anom(2050) -> 4.53

So far, so good.. i guess.... but

the problem; Plotting this   should give a graph between 0 and 5 when year y goes from 2000 to 2050

plot(y2anom(y), y = 2000 .. 2050)

But the graf becomes huge (size 10^10 ).  This is strange indeed...

```na := 8.069439677916595*10^5;
nb := -1.777065899098942*10^3;
nc := 1.467451715287991;
nd := -5.383733471268420*10^(-4);
ne := 7.404613067985871*10^(-8);
am := 0.77317633747818500000;
bm := -0.00626025741156560000;
cm := 0.00002185947833342660;
ap := 471.909671218139000000000000;
bp := -7.368938071612570000000000;
cp := 0.041111235018593800000000;
dp := -0.000098963929768727000000;
ep := 0.88147417256725300*10^(-7);
aq := 0.164489218115925*10^8;
bq := -32685.8887081463;
cq := 24.357113890912;
dq := -0.00806716031897729;
eq := 0.1001980162576*10^(-5);

y2ove(y) :=  ap + bp*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na) + cp*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na)^2 + dp*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na)^3 + ep*(ne*y^4 + nd*y^3 + nc*y^2 + nb*y + na)^4

y2anom(x) :=  (1/700)*int(y2ove(y), y = 2000 .. x);

```

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