## Why does pdsolve behave this way?...

Consider a standard initial/boundary value problem for the heat equation on the interval x ∈ [0,1]:

restart;
pde := diff(u(x,t),t) = diff(u(x,t),x,x);
ic := u(x,0) = f(x);
bc := u(0,t)=0,  u(1,t)=0;

Then
pdsolve({pde, ic, bc});
produces the expected Fourier series solution.

However, if we change the interval to x ∈ [-1,1], as in:
bc := u(-1,t)=0,  u(1,t)=0;
pdsolve({pde, ic, bc});

then Maple fails to return a solution.  Why?

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## Series Expansion...

Hello everyone.

Please I am trying to obtain series expansion of the expression below in u and v up to order 30 but encounter difficulties cum maple is slow to display solution. Can I get help on the code and what to do to optimize the displayed time of maple?

Thank you in anticipation of your quick and positive responses and suggestions.

convert(series(convert(series((y[n]+((-8 h u^2 v^2-4 u^3 sin(u) h+2 sin(2 u) h u^3+2 sin(2 v) h v^3-4 v^3 h sin(v)+2 v^3 h sin(2 u+v)+2 u^3 h sin(u-2 v)+2 u^3 h sin(u+2 v)-2 v^3 h sin(2 u-v)-u^3 h sin(2 u+2 v)-v^3 h sin(2 u+2 v)-u^3 h sin(2 u-2 v)+v^3 h sin(2 u-2 v)+4 h u^3 v^2 sin(2 u)+4 h u^2 v^3 sin(2 v)-4 h u^3 v^2 sin(u-v)+4 h u^2 v^3 sin(u-v)-4 h u^3 v^2 sin(u+v)-4 h u^2 v^3 sin(u+v)+4 h u^2 v^2 cos(u)+4 h u^2 v^2 cos(2 u)+4 h u^2 v^2 cos(2 v)+4 h u^2 v^2 cos(v)-4 h u^3 v cos(2 u-v)-2 h u^2 v^2 cos(2 u-v)+2 h u v^3 cos(2 u-v)+4 h u^3 v cos(2 u+v)-2 h u^2 v^2 cos(2 u+v)-2 h u v^3 cos(2 u+v)+2 h u^3 v cos(u-2 v)-2 h u^2 v^2 cos(u-2 v)-4 h u v^3 cos(u-2 v)-2 h u^3 v cos(u+2 v)-2 h u^2 v^2 cos(u+2 v)+4 h u v^3 cos(u+2 v)+4 h u^3 v cos(u-v)+4 h u v^3 cos(u-v)-4 h u^3 v cos(u+v)-4 h u v^3 cos(u+v)+4 u sin(u) v^2 h-2 sin(2 u) h u v^2-2 sin(2 v) h u^2 v+4 v h sin(v) u^2-2 v u^2 h sin(2 u+v)-2 u v^2 h sin(u-2 v)-2 u v^2 h sin(u+2 v)+2 v u^2 h sin(2 u-v)+v u^2 h sin(2 u+2 v)+u v^2 h sin(2 u+2 v)-v u^2 h sin(2 u-2 v)+u v^2 h sin(2 u-2 v)) f[n])/(-12 u^2 v^2+4 sin(u) u^3 v^2+4 sin(2 u) u^3 v^2+4 sin(2 v) u^2 v^3+4 sin(v) u^2 v^3-2 sin(2 u+v) u^3 v^2+2 sin(2 u+v) u^2 v^3-4 sin(u-v) u^3 v^2+4 sin(u-v) u^2 v^3-4 sin(u+v) u^3 v^2-4 sin(u+v) u^2 v^3+2 sin(u-2 v) u^3 v^2+2 sin(u-2 v) u^2 v^3+2 sin(u+2 v) u^3 v^2-2 sin(u+2 v) u^2 v^3-2 sin(2 u-v) u^3 v^2-2 sin(2 u-v) u^2 v^3+8 cos(u) u^2 v^2+4 cos(2 u) u^2 v^2+4 cos(2 v) u^2 v^2+8 cos(v) u^2 v^2-2 cos(2 u-v) u^3 v-4 cos(2 u-v) u^2 v^2-2 cos(2 u-v) u v^3+2 cos(2 u+v) u^3 v-4 cos(2 u+v) u^2 v^2+2 cos(2 u+v) u v^3-2 cos(u-2 v) u^3 v-4 cos(u-2 v) u^2 v^2-2 cos(u-2 v) u v^3+2 cos(u+2 v) u^3 v-4 cos(u+2 v) u^2 v^2+2 cos(u+2 v) u v^3-cos(2 u+2 v) u^3 v+2 cos(2 u+2 v) u^2 v^2-cos(2 u+2 v) u v^3+cos(2 u-2 v) u^3 v+2 cos(2 u-2 v) u^2 v^2+cos(2 u-2 v) u v^3+4 cos(u-v) u^3 v+4 cos(u-v) u v^3-4 cos(u+v) u^3 v-4 cos(u+v) u v^3)+((-8 h u^2 v^2+8 u^3 sin(u) h-4 sin(2 u) h u^3-4 sin(2 v) h v^3+8 v^3 h sin(v)-4 v^3 h sin(2 u+v)-4 u^3 h sin(u-2 v)-4 u^3 h sin(u+2 v)+4 v^3 h sin(2 u-v)+2 u^3 h sin(2 u+2 v)+2 v^3 h sin(2 u+2 v)+2 u^3 h sin(2 u-2 v)-2 v^3 h sin(2 u-2 v)+8 h u^3 v^2 sin(u)+8 h u^2 v^3 sin(v)-4 h u^3 v^2 sin(2 u+v)+4 h u^2 v^3 sin(2 u+v)+4 h u^3 v^2 sin(u-2 v)+4 h u^2 v^3 sin(u-2 v)+4 h u^3 v^2 sin(u+2 v)-4 h u^2 v^3 sin(u+2 v)-4 h u^3 v^2 sin(2 u-v)-4 h u^2 v^3 sin(2 u-v)+8 h u^2 v^2 cos(u)+8 h u^2 v^2 cos(v)+4 h u^3 v cos(2 u-v)-4 h u^2 v^2 cos(2 u-v)-8 h u v^3 cos(2 u-v)-4 h u^3 v cos(2 u+v)-4 h u^2 v^2 cos(2 u+v)+8 h u v^3 cos(2 u+v)-8 h u^3 v cos(u-2 v)-4 h u^2 v^2 cos(u-2 v)+4 h u v^3 cos(u-2 v)+8 h u^3 v cos(u+2 v)-4 h u^2 v^2 cos(u+2 v)-4 h u v^3 cos(u+2 v)-2 h u^3 v cos(2 u+2 v)+4 h u^2 v^2 cos(2 u+2 v)-2 h u v^3 cos(2 u+2 v)+2 h u^3 v cos(2 u-2 v)+4 h u^2 v^2 cos(2 u-2 v)+2 h u v^3 cos(2 u-2 v)-8 u sin(u) v^2 h+4 sin(2 u) h u v^2+4 sin(2 v) h u^2 v-8 v h sin(v) u^2+4 v u^2 h sin(2 u+v)+4 u v^2 h sin(u-2 v)+4 u v^2 h sin(u+2 v)-4 v u^2 h sin(2 u-v)-2 v u^2 h sin(2 u+2 v)-2 u v^2 h sin(2 u+2 v)+2 v u^2 h sin(2 u-2 v)-2 u v^2 h sin(2 u-2 v)) f[n+1])/(-12 u^2 v^2+4 sin(u) u^3 v^2+4 sin(2 u) u^3 v^2+4 sin(2 v) u^2 v^3+4 sin(v) u^2 v^3-2 sin(2 u+v) u^3 v^2+2 sin(2 u+v) u^2 v^3-4 sin(u-v) u^3 v^2+4 sin(u-v) u^2 v^3-4 sin(u+v) u^3 v^2-4 sin(u+v) u^2 v^3+2 sin(u-2 v) u^3 v^2+2 sin(u-2 v) u^2 v^3+2 sin(u+2 v) u^3 v^2-2 sin(u+2 v) u^2 v^3-2 sin(2 u-v) u^3 v^2-2 sin(2 u-v) u^2 v^3+8 cos(u) u^2 v^2+4 cos(2 u) u^2 v^2+4 cos(2 v) u^2 v^2+8 cos(v) u^2 v^2-2 cos(2 u-v) u^3 v-4 cos(2 u-v) u^2 v^2-2 cos(2 u-v) u v^3+2 cos(2 u+v) u^3 v-4 cos(2 u+v) u^2 v^2+2 cos(2 u+v) u v^3-2 cos(u-2 v) u^3 v-4 cos(u-2 v) u^2 v^2-2 cos(u-2 v) u v^3+2 cos(u+2 v) u^3 v-4 cos(u+2 v) u^2 v^2+2 cos(u+2 v) u v^3-cos(2 u+2 v) u^3 v+2 cos(2 u+2 v) u^2 v^2-cos(2 u+2 v) u v^3+cos(2 u-2 v) u^3 v+2 cos(2 u-2 v) u^2 v^2+cos(2 u-2 v) u v^3+4 cos(u-v) u^3 v+4 cos(u-v) u v^3-4 cos(u+v) u^3 v-4 cos(u+v) u v^3)+((-8 h u^2 v^2-4 u^3 sin(u) h+2 sin(2 u) h u^3+2 sin(2 v) h v^3-4 v^3 h sin(v)+2 v^3 h sin(2 u+v)+2 u^3 h sin(u-2 v)+2 u^3 h sin(u+2 v)-2 v^3 h sin(2 u-v)-u^3 h sin(2 u+2 v)-v^3 h sin(2 u+2 v)-u^3 h sin(2 u-2 v)+v^3 h sin(2 u-2 v)+4 h u^3 v^2 sin(2 u)+4 h u^2 v^3 sin(2 v)-4 h u^3 v^2 sin(u-v)+4 h u^2 v^3 sin(u-v)-4 h u^3 v^2 sin(u+v)-4 h u^2 v^3 sin(u+v)+4 h u^2 v^2 cos(u)+4 h u^2 v^2 cos(2 u)+4 h u^2 v^2 cos(2 v)+4 h u^2 v^2 cos(v)-4 h u^3 v cos(2 u-v)-2 h u^2 v^2 cos(2 u-v)+2 h u v^3 cos(2 u-v)+4 h u^3 v cos(2 u+v)-2 h u^2 v^2 cos(2 u+v)-2 h u v^3 cos(2 u+v)+2 h u^3 v cos(u-2 v)-2 h u^2 v^2 cos(u-2 v)-4 h u v^3 cos(u-2 v)-2 h u^3 v cos(u+2 v)-2 h u^2 v^2 cos(u+2 v)+4 h u v^3 cos(u+2 v)+4 h u^3 v cos(u-v)+4 h u v^3 cos(u-v)-4 h u^3 v cos(u+v)-4 h u v^3 cos(u+v)+4 u sin(u) v^2 h-2 sin(2 u) h u v^2-2 sin(2 v) h u^2 v+4 v h sin(v) u^2-2 v u^2 h sin(2 u+v)-2 u v^2 h sin(u-2 v)-2 u v^2 h sin(u+2 v)+2 v u^2 h sin(2 u-v)+v u^2 h sin(2 u+2 v)+u v^2 h sin(2 u+2 v)-v u^2 h sin(2 u-2 v)+u v^2 h sin(2 u-2 v)) f[n+2])/(-12 u^2 v^2+4 sin(u) u^3 v^2+4 sin(2 u) u^3 v^2+4 sin(2 v) u^2 v^3+4 sin(v) u^2 v^3-2 sin(2 u+v) u^3 v^2+2 sin(2 u+v) u^2 v^3-4 sin(u-v) u^3 v^2+4 sin(u-v) u^2 v^3-4 sin(u+v) u^3 v^2-4 sin(u+v) u^2 v^3+2 sin(u-2 v) u^3 v^2+2 sin(u-2 v) u^2 v^3+2 sin(u+2 v) u^3 v^2-2 sin(u+2 v) u^2 v^3-2 sin(2 u-v) u^3 v^2-2 sin(2 u-v) u^2 v^3+8 cos(u) u^2 v^2+4 cos(2 u) u^2 v^2+4 cos(2 v) u^2 v^2+8 cos(v) u^2 v^2-2 cos(2 u-v) u^3 v-4 cos(2 u-v) u^2 v^2-2 cos(2 u-v) u v^3+2 cos(2 u+v) u^3 v-4 cos(2 u+v) u^2 v^2+2 cos(2 u+v) u v^3-2 cos(u-2 v) u^3 v-4 cos(u-2 v) u^2 v^2-2 cos(u-2 v) u v^3+2 cos(u+2 v) u^3 v-4 cos(u+2 v) u^2 v^2+2 cos(u+2 v) u v^3-cos(2 u+2 v) u^3 v+2 cos(2 u+2 v) u^2 v^2-cos(2 u+2 v) u v^3+cos(2 u-2 v) u^3 v+2 cos(2 u-2 v) u^2 v^2+cos(2 u-2 v) u v^3+4 cos(u-v) u^3 v+4 cos(u-v) u v^3-4 cos(u+v) u^3 v-4 cos(u+v) u v^3)+((-6 u^2 h^2-6 v^2 h^2-4 cos(2 u) h^2 u^2 v^2-4 cos(2 v) h^2 u^2 v^2+8 v^2 u^2 h^2 cos(u-v)+8 v^2 u^2 h^2 cos(u+v)+8 u sin(u) v^2 h^2+8 sin(2 u) h^2 u v^2+8 sin(2 v) h^2 u^2 v+8 v h^2 sin(v) u^2+4 v u^2 h^2 sin(2 u+v)-4 u v^2 h^2 sin(2 u+v)+8 v u^2 h^2 sin(u-v)-8 sin(u-v) h^2 u v^2-8 v u^2 h^2 sin(u+v)-8 sin(u+v) h^2 u v^2+4 v u^2 h^2 sin(u-2 v)+4 u v^2 h^2 sin(u-2 v)-4 v u^2 h^2 sin(u+2 v)+4 u v^2 h^2 sin(u+2 v)-4 v u^2 h^2 sin(2 u-v)-4 u v^2 h^2 sin(2 u-v)-4 u v h^2 cos(2 u-v)+4 u v h^2 cos(2 u+v)-4 u v h^2 cos(u-2 v)+4 u v h^2 cos(u+2 v)-2 u v h^2 cos(2 u+2 v)+2 u v h^2 cos(2 u-2 v)+8 cos(u-v) h^2 u v-8 cos(u+v) h^2 u v-8 v^2 u^2 h^2+8 h^2 cos(u) u^2-2 cos(2 u) h^2 u^2+6 cos(2 u) h^2 v^2+6 cos(2 v) h^2 u^2-2 cos(2 v) h^2 v^2+8 h^2 cos(v) v^2-4 v^2 h^2 cos(2 u-v)-4 v^2 h^2 cos(2 u+v)-4 u^2 h^2 cos(u-2 v)-4 u^2 h^2 cos(u+2 v)+u^2 h^2 cos(2 u+2 v)+v^2 h^2 cos(2 u+2 v)+u^2 h^2 cos(2 u-2 v)+v^2 h^2 cos(2 u-2 v)) g[n])/(-12 u^2 v^2+4 sin(u) u^3 v^2+4 sin(2 u) u^3 v^2+4 sin(2 v) u^2 v^3+4 sin(v) u^2 v^3-2 sin(2 u+v) u^3 v^2+2 sin(2 u+v) u^2 v^3-4 sin(u-v) u^3 v^2+4 sin(u-v) u^2 v^3-4 sin(u+v) u^3 v^2-4 sin(u+v) u^2 v^3+2 sin(u-2 v) u^3 v^2+2 sin(u-2 v) u^2 v^3+2 sin(u+2 v) u^3 v^2-2 sin(u+2 v) u^2 v^3-2 sin(2 u-v) u^3 v^2-2 sin(2 u-v) u^2 v^3+8 cos(u) u^2 v^2+4 cos(2 u) u^2 v^2+4 cos(2 v) u^2 v^2+8 cos(v) u^2 v^2-2 cos(2 u-v) u^3 v-4 cos(2 u-v) u^2 v^2-2 cos(2 u-v) u v^3+2 cos(2 u+v) u^3 v-4 cos(2 u+v) u^2 v^2+2 cos(2 u+v) u v^3-2 cos(u-2 v) u^3 v-4 cos(u-2 v) u^2 v^2-2 cos(u-2 v) u v^3+2 cos(u+2 v) u^3 v-4 cos(u+2 v) u^2 v^2+2 cos(u+2 v) u v^3-cos(2 u+2 v) u^3 v+2 cos(2 u+2 v) u^2 v^2-cos(2 u+2 v) u v^3+cos(2 u-2 v) u^3 v+2 cos(2 u-2 v) u^2 v^2+cos(2 u-2 v) u v^3+4 cos(u-v) u^3 v+4 cos(u-v) u v^3-4 cos(u+v) u^3 v-4 cos(u+v) u v^3)+((6 u^2 h^2+6 v^2 h^2+4 cos(2 u) h^2 u^2 v^2+4 cos(2 v) h^2 u^2 v^2-8 v^2 u^2 h^2 cos(u-v)-8 v^2 u^2 h^2 cos(u+v)-8 u sin(u) v^2 h^2-8 sin(2 u) h^2 u v^2-8 sin(2 v) h^2 u^2 v-8 v h^2 sin(v) u^2-4 v u^2 h^2 sin(2 u+v)+4 u v^2 h^2 sin(2 u+v)-8 v u^2 h^2 sin(u-v)+8 sin(u-v) h^2 u v^2+8 v u^2 h^2 sin(u+v)+8 sin(u+v) h^2 u v^2-4 v u^2 h^2 sin(u-2 v)-4 u v^2 h^2 sin(u-2 v)+4 v u^2 h^2 sin(u+2 v)-4 u v^2 h^2 sin(u+2 v)+4 v u^2 h^2 sin(2 u-v)+4 u v^2 h^2 sin(2 u-v)+4 u v h^2 cos(2 u-v)-4 u v h^2 cos(2 u+v)+4 u v h^2 cos(u-2 v)-4 u v h^2 cos(u+2 v)+2 u v h^2 cos(2 u+2 v)-2 u v h^2 cos(2 u-2 v)-8 cos(u-v) h^2 u v+8 cos(u+v) h^2 u v+8 v^2 u^2 h^2-8 h^2 cos(u) u^2+2 cos(2 u) h^2 u^2-6 cos(2 u) h^2 v^2-6 cos(2 v) h^2 u^2+2 cos(2 v) h^2 v^2-8 h^2 cos(v) v^2+4 v^2 h^2 cos(2 u-v)+4 v^2 h^2 cos(2 u+v)+4 u^2 h^2 cos(u-2 v)+4 u^2 h^2 cos(u+2 v)-u^2 h^2 cos(2 u+2 v)-v^2 h^2 cos(2 u+2 v)-u^2 h^2 cos(2 u-2 v)-v^2 h^2 cos(2 u-2 v)) g[n+2])/(-12 u^2 v^2+4 sin(u) u^3 v^2+4 sin(2 u) u^3 v^2+4 sin(2 v) u^2 v^3+4 sin(v) u^2 v^3-2 sin(2 u+v) u^3 v^2+2 sin(2 u+v) u^2 v^3-4 sin(u-v) u^3 v^2+4 sin(u-v) u^2 v^3-4 sin(u+v) u^3 v^2-4 sin(u+v) u^2 v^3+2 sin(u-2 v) u^3 v^2+2 sin(u-2 v) u^2 v^3+2 sin(u+2 v) u^3 v^2-2 sin(u+2 v) u^2 v^3-2 sin(2 u-v) u^3 v^2-2 sin(2 u-v) u^2 v^3+8 cos(u) u^2 v^2+4 cos(2 u) u^2 v^2+4 cos(2 v) u^2 v^2+8 cos(v) u^2 v^2-2 cos(2 u-v) u^3 v-4 cos(2 u-v) u^2 v^2-2 cos(2 u-v) u v^3+2 cos(2 u+v) u^3 v-4 cos(2 u+v) u^2 v^2+2 cos(2 u+v) u v^3-2 cos(u-2 v) u^3 v-4 cos(u-2 v) u^2 v^2-2 cos(u-2 v) u v^3+2 cos(u+2 v) u^3 v-4 cos(u+2 v) u^2 v^2+2 cos(u+2 v) u v^3-cos(2 u+2 v) u^3 v+2 cos(2 u+2 v) u^2 v^2-cos(2 u+2 v) u v^3+cos(2 u-2 v) u^3 v+2 cos(2 u-2 v) u^2 v^2+cos(2 u-2 v) u v^3+4 cos(u-v) u^3 v+4 cos(u-v) u v^3-4 cos(u+v) u^3 v-4 cos(u+v) u v^3)),u=0,32),polynom),v=0,32),polynom);

## asymptotic expansion of f ...

In some cases, maple is able to return a series expansion when line A is called but fails to do so when line B is called, and in the help page for asympt it defines them to be identical procedures:

A: asympt(f,z)

B:

this has generally occured when ever the function f is of the form:

where g(z) has an asymptotic expansion and when asympt(f,z) is called, maple provides this expansion divided by the exponential function, however line B as prescribed above returns an error.

So, my question is, which line in showstat(asympt) is responsible for catching the error which line B as above encounters?

## how to find back the term in summation?...

Lee := (-1+Int(exp(LambertW(1/(-1+t))*(-1+t)), t=1..x))/(Int(exp(LambertW(1/(-1+t))*(-1+t)), t=1..x));
sum(unknown, n=1..infinity) = Lee

how to find unknown?

## The Series function...

The image is an extract from the help page on the function "series" my question is in regard to how a method is selected, ie either it be a taylor or laurent series expansion, or as it defines in the passage attached "a more generalised series".

im just curious to know what procedure maple uses to make this choice when the series function is called, and im also finding it hard to replicate and understand the procedure of computing coeffiecents as described in the extract for a generalised series.

Thanks.

## How to convert series functions back to it origina...

Good morning sirs,

Anyone with the idea(s) on how to convert series back to its original form should please share with me.

Take for example

a-(1/2)*beta*a^2*y^2+(1/24)*beta^2*a^3*y^4-(1/720)*beta^3*a^4*y^6+(1/40320)*beta^4*a^5*y^8-(1/3628800)*beta^5*a^6*y^10+(1/479001600)*beta^6*a^7*y^12-(1/87178291200)*beta^7*a^8*y^14+O(y^16)

is a series for a*cos(sqr(a*beta)*y)

## different asymptotics using asympt and Multiseries...

Hey guys,

I have the following occurence:

ii_inf:=x^(2-s)*(x^(-s)*GAMMA(3-s)*GAMMA(2-2*s)/(GAMMA(2-s)*GAMMA(3-2*s))+x^(s-2)*GAMMA(3-s)*GAMMA(2*s-2)/GAMMA(s))/(2-s)+(1/2)*(2*s*x-x+1)*(x+1)/(((x+1)^s)^2*(2*s^2-3*s+1))+x^(1-s)*(x^(-s)*GAMMA(2-s)*GAMMA(-2*s+1)/(GAMMA(1-s)*GAMMA(2-2*s))+x^(-1+s)*GAMMA(2-s)*GAMMA(2*s-1)/GAMMA(s))/(1-s)+(x+1)/((2*s-1)*((x+1)^s)^2)+x/((-1+s)*x^s)-(x+1)/((-1+s)*(x+1)^s);

ii_inf=simplify(ii_inf);

asympt(ii_inf,x,3);

Multiseries:-asympt(ii_inf,x,1);
gives different results...the last one however seems to be the correct one...

What is happening here?

## How do I convert a series to trigonometry or hyper...

theta := a-(1/2)*beta*a*y^2+(1/24)*beta^2*a*y^4-(1/720)*beta^3*a*y^6+(1/40320)*beta^4*a*y^8-(1/3628800)*beta^5*a*y^10+(1/479001600)*beta^6*a*y^12-(1/87178291200)*beta^7*a*y^14+(1/20922789888000)*beta^8*a*y^16-(1/6402373705728000)*beta^9*a*y^18+(1/2432902008176640000)*beta^10*a*y^20-(1/1124000727777607680000)*beta^11*a*y^22+(1/620448401733239439360000)*beta^12*a*y^24

Pls, anyone with useful informations on how to convert a series just like the one above to trigonometry or hyperbolic form. Need response as soon as possible. Thankin you in anticipation for your favorable response.

## integral of erfc(x)...

I am trying to calculate the integral

where

Maple cannot calculate the integral. I tried to expand theta in the series form and substitute in the integral, still cannot calculate it.

any suggestion to tackle this problem whould be helpful.

Thank you

## asymptomatic series expansion ...

so yep pretty self explainatory, i was just wondering why it works when i use the asymptomatic expansion but not the iterated reciprocal substitution code shown in the that help interface for asympt.

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## Has someone ever written an "mseries" function?...

I am dealing relatively often with vector functions of a variable vector. Specifically these are (in general nonlinear) mappings from R^6 to R^6, and often I have one or more extra parameter that controls the map.

Often I'd like to get a first-order expansion of these. The general scheme I use to do that is to map mtaylor over the components of the function vector. Like so:

map(mtaylor,F(<x1...x6>),[x1...x6,p1...pn],order);# F(<...>)  is  <F1(<..>)..F6(<...>)>

This works fine until I hit a situation where the Taylor expansion for one of the parameters p does not exist. Then it bombs. Actually, I often can use assumptions on the parameters to prevent bombing; however, in that case I often get the unchanged function F returned. This is Bad as the whole thing happens in a loop with many concatenated functions F, and now expression swell makes Maple lock up.

In at least a significant subset of these functions, the series command works where taylor fails. "mseries", however, does not exist in Maple. So my question is whether someone has written an "mseries" command for Maple. I know how to do it in principle (but caution is needed to make it work as intended), however, I wonder whether either someone has done it before and might share his/her code, or whether there is a reason why "mseries" actually cannot work.

TIA,

Mac Dude