in Maple 2022.1 on windows 10

Why it happens and is there a workaround?

Does it happen on earlier versions? I do not have an earlier Maple installed on my current PC as it is new to check. 

Download int_problem_8_10_2022.mw

I have string of length

StringTools:-Length(str);
                            1073105

When doing

p:=StringTools:-LengthSplit(str,100):

Maple gives

From help:

LengthSplit
split a string into equal length pieces
 

This is all done in .mpl  file actually, not interactive, but I made the above worksheet to show  the problem. The string is read from a file by a program and it wants to split it to 100 length smaller strings.

I have lots of RAM. 128 GB.  So why does Maple crash and is there a workaround this?

This string was generated by another software.

I have attached the above example below as worksheet.  Maple 2022.1 on windows 10.

Here is a simpler way to generate this problem

restart;
str:=StringTools:-Random(1073104,'upper'):
str[1..10];

StringTools:-Length(str);
p:=StringTools:-LengthSplit(str,100):

Using trial and error, the crash happens when the length reaches 1073101. At 1073100 there was no crash.

Found case where PDEtools:-Solve gives exception but not solve.

Is this known issue?

Download exception_from_Solve_august_8_2022.mw

I create a plot, then later on, I want to use the same view for a second plot or using the same starting x, ending x and starting y and ending y. For reasons no need to get into into, I need to do this and I have no access to this information at this time. I only have access to the p variable used to store the plot into as in this example below.

I am not sure what is the correct way to do read this information from the PLOTS structure as I never used it before. 

Help describes the PLOTS structure under "PLOT and PLOT3D Data Structures" , but do not see how is one supposed to read different parts of it. I could have missed it. Maple help pages are very hard for me to read in order to obtain the information needed. From help it says:

The Maple plotting functions, plot, plot3d, and others, produce PLOT and PLOT3D data structures describing the images to be displayed.

By trial and error, for standard plot this worked

p:=plot(sin(x),x=-1..10):
op([4,1,2,2],p)

returns

           "originalview" = [-0.9862500000 .. 9.9862500000, -1.0000000000 .. 1.0000000000]

I see also that command plottools:-getdata(p):  returns the data. So I could also do (it is stored in matrix, in third entry):

p0:=plottools:-getdata(p);
startingx:=p0[3][1,1];
startingy:=p0[3][1,2];
endingx:=p0[3][-1,1];
endingy:=p0[3][-1,2];

Will the above work all the time? should this command be used to obtain this information or is there a better way?

When I lprint(p) I see these fields have actual names. For example  , here is screen shot of lprint(p)  

it looks like  a RECORD data structure. But when I tried p:-originalview  Error, `p` does not evaluate to a module 

The question is: What is the correct way to find what x range and y range was used for an earlier plot, given one has access only to p variable used to store the output of the plot command?  This is for 2D plot only.

I have differential equation with x as independent variable that I want to convert to state space representation.

But DynamicSystems will not accept y(x) as the output variable, since it defaults to y(t).

Help under "Description of the Model of a Linear System Object" says it is possible to change the independent variable by changing continuoustimevar setting. But help does not give an example how to do this and all my tries failed.

How to do this? Attached is worksheet showing the problem

Download DS_problem.mw