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The command, "diff(expr, var, [Order])," is designed to return derivatives of a specified order; but [Order] does not support a {list} as an argument for the Order option. Is there a convenient way to obtain a list, (or a range), of the derivatives of an expression? (This might be useful for identifying patterns in a series, etc.).

[CAS] Example:
f(x):=ln(x); // ==> {x^-1, -1* x^-2, 2*x^-3 }, With the first three derivatives as the desired "Order."

f'(x);
f''(x);
f'''(x);

-or-

diff(f(x),x,1);
diff(f(x),x,2);
diff(f(x),x,3);

Objective: Obtain a list of the derivatives of an expression from a single command.

Thanks!

-Dale-

(06-13-2018 10:28 AM)DrD Wrote: [ -> ]Objective: Obtain a list of the derivatives of an expression from a single command.

map([1,2,3],j->diff(f(x),x,j))
or
apply(j->diff(f(x),x,j),[1,2,3])

Very nice! Thanks, Didier!

-Dale-