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Hello there! Maple 2016.1 sometimes gets crasy about parsing input strings. I managed to capture this behaviour in the attached file. It looks like below. I am not sure what exactly triggers it. It just starts happening all of a sudden. What might be the cause...? 


"1 Pi"

Error, incorrect syntax in parse: `;` unexpected (near 4th character of parsed string)

"1 Pi"



Error, invalid semantics "π"




Error, incorrect syntax in parse: `;` unexpected (near 4th character of parsed string)






In workbook mode I use the Insert>>Paragaph>>Before Cursor to create a text block. I just want to type text into this block by way of comments on what preceded/follows. However, when I type parentheses or <> of (I expect) other stuff that Maple recognises as being parts of mathematical expressions Maple switches to italic and bold and starts generally interefering with my text. In the case of my title I get the result in the picture below. Is there any way to stop Maple doing this so I can type text?


Here is my Maple 16 code:

 I expected to get outuput

a [a,b,c]

a [a,c,b]

But I get no output.





So I am trying to apply the Optimization function to a rather complicated problem I am currently working on, and having some trouble getting maple to cooporate. This is the part of the code that is giving me the error, with error included. All of the variables imputtet when calling OptimizeSpring are constants. If there is any other details I should add, please say so and I will add them promptly :) Thanks alot!
Maple problem

I suspect that it might be related to this suggestion, but I am not sure how to apply it



wondered if anyone knows how to make proper use of the large operators pallete on the list of pallettes on the left. For example when using the contour integration symbol on the left how do you enter the delimiters. 

I always get the error: "Error, unable to match delimiters". The help on this is not useful for this case. 




Error, invalid piecewise


is OK.

Hi. I have this strange error.

Whenever I type D(f)(x) into the maple prompt, the program adds a whitespace between D(f) and (x), so I get the wrong output. I have to go back and delete the space manually. Here is a picture.

I type 'D(f)(x)'  and the software displays 'D(f) (x) ' in the prompt, with the extra space.

I am using maple 2015 if that helps, but I think I had the same error with Maple 18

I did not add a space. I literally just entered f:=x->x^2 -3*x + 2; D(f)(x)

but the computer adds a space as I type D(f)(x).

Also I'm not sure why the space ruins the expression

What i am supposed to get is  ' 2x - 3 '


I am a Maple 15 Student Edition user on both Windows and Linux. I wonder if it is possible to see the actual command send to Maple when I click on a particular entry in the right click context menu. If it is possible to do so, how can I have it displayed in document/worksheet mode? Does it matter if I am inputting in 1D or 2D?

Thanks in advance

i have the following equation:

1.003225155^(l)-((&int;)[0]^1[((((0.6 r^2+1)^1.813666667)/((0.375 r^2+1)^2.666666667))^())^(l)r &DifferentialD;r)=0


and throws me the error:

Error, Got internal error in unknown : "invalid input: lhs received sattr, which is not valid for its 1st argument, expr"


do  you know the meaning of the error and why this equation cant be solved for l?

i noticed members use such tags in their post very rarely in mapleprimes

and i am confused whether ?

there is a list of special html tags that are supported in "HTML Source Editor" of mapleprimes

that are compatible with it ? or all tags described in html5 or html4 are compatible ?

i just tested a few of those tags and they work excellent ...



I would like to display mathematical expressions on a plot.


I am using the following command on the code edit region of Maple 15 worksheet, intending to show the maths on a plot.

t := plots:-textplot([x, y, typeset(a[0]=1)], align = above): #where x and y are the position



is the series expansion for the following expression bugged in maple or am I missing some crucial thing of series?


results in epsilon^-1 -2 -2*ln(2)

for xmaple 16.01. The console version does not add the wrong term "-2".

Apparently it works here: 

How does one change a previous Atomic setting back to non-Atomic?  This seems so simple, but I can't find anyway to Undo this change.  


I am using Maple 11.  When I set up an equation, I can see an easy solution by visual inspection but when I have Maple solve the equation then use real numbers the results are different!  What is going on??  I have uploaded my worksheet which shows the discrepancy. 



Apart from the online description of this new Maple 16 feature here, there is also the help-page for subexpressionmenu.

I don't know of a complete listing of its current functionality, but the key thing is that it acts in context. By that I mean that the choice of displayed actions depends on the kind of subexpression that one has selected with the mouse cursor.

Apart from arithmetic operations, rearrangements and some normalizations of equations, and plot previews, one of the more interesting pieces of functionality is the various trigonometric substitutions. Some of the formulaic trig substitutions provide functionality that has otherwise been previously (I think) needed in Maple.

In Maple 16 it is now much easier to do some trigonometric identity solving, step by step.

Here is an example executed in a worksheet. (This was produced by merely selecting subexpressions of the output at each step, and waiting briefly for the new Smart Popup menus to appear automatically. I did not right-click and use the traditional context-sensitive menus. I did not have to type in any of the red input lines below: the GUI inserts them as a convenience, for reproduction. This is not a screen-grab movie, however, and doesn't visbily show my mouse cursor selections. See the 2D Math version further below for an alternate look and feel.)



sin(3*a) = 3*sin(a)-4*sin(a)^3

# full angle reduction identity: sin(3*a)=-sin(a)^3+3*cos(a)^2*sin(a)
-sin(a)^3+3*cos(a)^2*sin(a) = 3*sin(a)-4*sin(a)^3;

-sin(a)^3+3*cos(a)^2*sin(a) = 3*sin(a)-4*sin(a)^3

# subtract -sin(a)^3 from both sides
(-sin(a)^3+3*cos(a)^2*sin(a) = 3*sin(a)-4*sin(a)^3) -~ (-sin(a)^3);

3*cos(a)^2*sin(a) = 3*sin(a)-3*sin(a)^3

# divide both sides by 3
(3*cos(a)^2*sin(a) = 3*sin(a)-3*sin(a)^3) /~ (3);

cos(a)^2*sin(a) = sin(a)-sin(a)^3

# divide both sides by sin(a)
(cos(a)^2*sin(a) = sin(a)-sin(a)^3) /~ (sin(a));

cos(a)^2 = (sin(a)-sin(a)^3)/sin(a)

# normal 1/sin(a)*(sin(a)-sin(a)^3)
cos(a)^2 = normal(1/sin(a)*(sin(a)-sin(a)^3));

cos(a)^2 = 1-sin(a)^2

# Pythagoras identity: cos(a)^2=1-sin(a)^2
1-sin(a)^2 = 1-sin(a)^2;

1-sin(a)^2 = 1-sin(a)^2


The very first step above could also be done as a pair of simpler sin(x+y) reductions involving sin(2*a+a) and sin(a+a), depending on what one allows onself to use. There's room for improvement to this whole approach, but it looks like progress.


In a Document, rather than using 1D Maple notation in a Worksheet as above, the actions get documented in the more usual way, similar to context-menus, with annotated arrows between lines.

expr := sin(3*a) = 3*sin(a)-4*sin(a)^3:


sin(3*a) = 3*sin(a)-4*sin(a)^3


2*cos(a)*sin(2*a)-sin(a) = 3*sin(a)-4*sin(a)^3


4*cos(a)^2*sin(a)-sin(a) = 3*sin(a)-4*sin(a)^3


4*cos(a)^2*sin(a) = 4*sin(a)-4*sin(a)^3


cos(a)^2*sin(a) = sin(a)-sin(a)^3


cos(a)^2 = (sin(a)-sin(a)^3)/sin(a)


cos(a)^2 = 1-sin(a)^2


1-sin(a)^2 = 1-sin(a)^2


1 = 1




I am not quite sure what is the best way to try and get some of the trig handling in a more programmatic way, ie. by using the "names" of the various transformational formulas. But some experts here may discover such by examination of the code. Ie,



The above can leads to noticing the following (undocumented) difference, for example,

> trigsubs(sin(2*a));
                                 1       2 tan(a)
[-sin(-2 a), 2 sin(a) cos(a), --------, -----------,
                              csc(2 a)            2
                                        1 + tan(a)

    -1/2 I (exp(2 I a) - exp(-2 I a)), 2 sin(a) cos(a), 2 sin(a) cos(a)]

> trigsubs(sin(2*a),annotate=true);

["odd function" = -sin(-2 a), "double angle" = 2 sin(a) cos(a),

                               1                       2 tan(a)
    "reciprocal function" = --------, "Weierstrass" = -----------,
                            csc(2 a)                            2
                                                      1 + tan(a)

    "Euler" = -1/2 I (exp(2 I a) - exp(-2 I a)),

    "angle reduction" = 2 sin(a) cos(a),

    "full angle reduction" = 2 sin(a) cos(a)]

And that could lead one to try constructions such as,

> map(rhs,indets(trigsubs(sin(a),annotate=true),
>                identical("double angle")=anything));

                             {2 sin(a/2) cos(a/2)}

Since the `annotate=true` option for `trigsubs` is not documented in Maple 16 there is more potential here for useful functionality.

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