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Sometimes when I do, for example, a series expansion Mathematica gives me output that it won't take as input. For example if I do a series expansion:

Series[Hypergeometric2F1[a,x,y,z], {a,0,0} ]

produces:

Out[xx]= 1+ a Hypergeometric2F1^(1,0,0,0)[0,x,y,z] + O[a]^2

If I literally then click on this cell and evaluate it as input, or alternatively cut and paste this term into another input line and evaluate it returns the following error:

Syntax::sntxf: "(" cannot be followed by "1,0,0,0)".

Syntax::sntxi: Incomplete expression; more input is needed .

So it doesn't seem to like the exact form as input that it just gave me as output. What gives?

EDITS:

1) I apologize for the formatting errors in the posting and the confusion that resulted, that should be fixed now. Thank you to those that pointed them out.

2) I have tried the suggestions to use InputForm[%]-the thing this, the expressions I am dealing with are very long, and when I put it into input-form they become unwieldy. I would prefer a way to retain the standard-form expression and manipulate that - but this might be impossible (it seems like it is impossible).

Thanks for the help so far anyway.

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  • $\begingroup$ This indicates that you took derivatives in the wrong way somewhere. To track it down, you have to provide a minimal example of the code that produced this output line. $\endgroup$
    – Jens
    Jun 6, 2012 at 15:27
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    $\begingroup$ Some types of output can't be interpreted as input if you re-type them yourself. One example would be $f^{(1,0)}[x]$. However, when these are produced as output, they usually contain hidden information (in the form of a TagBox) that allows the system to interpret them again without ambiguity, even if you copy and paste them in full. Try for example evaluating Derivative[1, 0][f][x] to produce such an output. If you copy and paste them partially, or edit them, this information may get lost. $\endgroup$
    – Szabolcs
    Jun 6, 2012 at 15:30
  • $\begingroup$ Please include Mathematica-Code as Code in your post. Click on the help button in the editor to see how this works. $\endgroup$
    – halirutan
    Jun 6, 2012 at 15:48
  • $\begingroup$ HypergeometricF1 isn't a Mathematica function. Do you mean Hypergeometric2F1? $\endgroup$ Jun 6, 2012 at 15:51
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    $\begingroup$ The safest method to copy previous output is to use the key combo Shift+Ctrl+L; that way, any (invisible) formatting is preserved. $\endgroup$ Jun 6, 2012 at 16:00

2 Answers 2

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Use InputForm to get something you always can copy&paste:

Series[Hypergeometric2F1[\[Epsilon], x, y, z], {\[Epsilon], 0, 1}]//InputForm
(*
==> SeriesData[\[Epsilon], 0, {1,
    Derivative[0, 1, 0, 0][Hypergeometric2F1][x, 0, y, z]}, 0, 2, 1]
*)

If you want it as normal expression, use //Normal//InputForm instead.

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You need to convert the power series into a normal expression using

Series[Hypergeometric2F1[\[Epsilon],x,y,z], {\[Epsilon],0,1}]//Normal 
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  • $\begingroup$ Actually I did this in the actual code myself but it doesn't help. I just left it out here. As you can see from the errors the problem is with the (0,1,0,0). Thanks for the help though. $\endgroup$
    – DJBunk
    Jun 6, 2012 at 16:35

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