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labels for plots do not use Typesetting....

nm 11643 Maple 2024
typesetting label deplot
August 07 2024
2 0

For display of plot axes labels, I prefer to use the Typesseting in place so that diff(y(x),x) display as y'(x) (takes less space and looks better also).

It does that in the worksheet. But when using diff(y(x),x) as the Y axis label, the plot still shows diff(y(x),x) and not y'(x).

Is there a way to make plot and DEtools:-DEplot  use the Typesetting in place?   What is the point of using Typesetting if plots generated do not use it?
 

> 

interface(version);

`Standard Worksheet Interface, Maple 2024.1, Windows 10, June 25 2024 Build ID 1835466`

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1781 and is the same as the version installed in this computer, created 2024, August 4, 11:27 hours Pacific Time.`

> 

restart;
> 

interface(typesetting = extended)

extended

> 

Typesetting:-Settings(prime=x,'typesetprime'=true); #this says to use y'(x) instead of dy/dx    
#Typesetting:-Suppress(y(x)); # this says to use y' and not y'(x)

x, false

> 

#phase plot for second order ode. Y axis is y'(x) and X axis is y(x)
#uses DynamicsSystems for conversion.
ode := diff(y(x),x$2) = -y(x)-1/2*diff(y(x),x);   
DynamicSystems:-SystemOptions('statevariable'=sv):
DynamicSystems:-SystemOptions('discretefreqvar'=ssv):            
DynamicSystems:-SystemOptions('outputvariable'=sssv):
DynamicSystems:-SystemOptions('continuoustimevar'=ssssv):  

DynamicSystems:-SystemOptions('continuoustimevar'=x):            
sys:=DynamicSystems:-DiffEquation(ode,'outputvariable'=[y(x)]):

sys0:=DynamicSystems:-StateSpace(sys):
eq1:=diff(X1(x),x)=sys0:-a[1,..].Vector([X1(x),X2(x)]):
eq2:=diff(X2(x),x)=sys0:-a[2,..].Vector([X1(x),X2(x)]):

DEtools:-DEplot([eq1,eq2],[X1(x),X2(x)],x=0..100,
            X2=-4..4,X1=-4..4,
            axes=boxed,
            linecolor = red,        
            labels=[y(x),diff(y(x),x)]);
 

diff(diff(y(x), x), x) = -y(x)-(1/2)*(diff(y(x), x))

> 

 


 

Download labels_for_plot_do_not_use_typesetting_maple_2024.mw

 

Notice the label on Y axis above. I'd like that to display as y'(x) as it is in the worksheet.

 

any one gets their Maple desktop become ...

nm 11643 Maple 2024
monitor installation
August 07 2024
0 9

I noticed very serious problem in Maple 2024.1

This is new windows 10  22H2  installation. With Maple 2024.1. I've only seen this using Maple and no other windows applications. I have 2 monitors and NVIDIA GeForce RTX 3060 graphics card.

What happens is that sometimes (may be 2-3 times each day), Maple frontend gets all mangled up. I could not figure what causes it. it could be when I move the window from one terminal to the other. sometimes it happens when I open a debugger window.

Only way to fix this is to close all of Maple and start it again. 

Just wondering if anyone seen anything like this and what can cause it. Again, it is only Maple that shows this problem, no other windows application does this. Have 128 GB Ram and PC is only 2 years old.

This is the very first time I see this in Maple and used Maple for long time and on this same PC before and had two terminals also before all the time. I have no idea what causes it.

Could it be Java problem in Maple 2024.1 ?

internal error (in is/internal) type d...

nm 11643 Maple 2024
solve error
August 06 2024
0 1

Any idea why calling solve(eqs,unknowns) gives Error, (in is/internal) type does not exist when the unknowns are in a set, but the error goes away when the unknowns are in a list? Is this expected or is this a bug?


 

> 

interface(version);

`Standard Worksheet Interface, Maple 2024.1, Windows 10, June 25 2024 Build ID 1835466`

> 

Physics:-Version()

`The "Physics Updates" version in the MapleCloud is 1779 and is the same as the version installed in this computer, created 2024, July 25, 8:56 hours Pacific Time.`

> 

restart;
> 

eqs:={0 = ln(2)+ln(-a*sech(1/2*2^(1/2)*b)^2), 1 = -tanh(1/2*2^(1/2)*b)*a^(1/2)*2^(1/2)};
unknown:={a, b};

{0 = ln(2)+ln(-a*sech((1/2)*2^(1/2)*b)^2), 1 = -tanh((1/2)*2^(1/2)*b)*a^(1/2)*2^(1/2)}

{a, b}

> 

solve(eqs,unknown)

Error, (in is/internal) type `a` does not exist

> 

solve(eqs,unknown)

Error, (in is/internal) type `a` does not exist

> 

restart;
> 

eqs:=[0 = ln(2)+ln(-a*sech(1/2*2^(1/2)*b)^2), 1 = -tanh(1/2*2^(1/2)*b)*a^(1/2)*2^(1/2)];
unknown:={a, b};

[0 = ln(2)+ln(-a*sech((1/2)*2^(1/2)*b)^2), 1 = -tanh((1/2)*2^(1/2)*b)*a^(1/2)*2^(1/2)]

{a, b}

> 

solve(eqs,unknown)

Error, (in is/internal) type `a` does not exist

> 

restart;
> 

eqs:=[0 = ln(2)+ln(-a*sech(1/2*2^(1/2)*b)^2), 1 = -tanh(1/2*2^(1/2)*b)*a^(1/2)*2^(1/2)];
unknown:=[a, b];

[0 = ln(2)+ln(-a*sech((1/2)*2^(1/2)*b)^2), 1 = -tanh((1/2)*2^(1/2)*b)*a^(1/2)*2^(1/2)]

[a, b]

> 

solve(eqs,unknown)

[]

> 

 


 

Download is_internal_error_from_solve_maple_2024_1.mw

Update

Reported to Maplesoft support.

 

limit not evaluating...

nm 11643 Maple 2024
limit
August 05 2024
2 1

Any idea why limit(e,x=0) fail to evaluate but  eval(e,x=0) does in this example? 

> 

interface(version);

`Standard Worksheet Interface, Maple 2024.1, Windows 10, June 25 2024 Build ID 1835466`

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1779 and is the same as the version installed in this computer, created 2024, July 25, 8:56 hours Pacific Time.`

> 

restart;
> 

e:=-tanh(sqrt(2)*(a*x+b))

-tanh(2^(1/2)*(a*x+b))

> 

limit(e,x=0)

limit(-tanh(2^(1/2)*(a*x+b)), x = 0)

> 

eval(e,x=0)

-tanh(b*2^(1/2))

> 

 

 

Download limit_problem_maple_2024_1.mw

I tried the above using some other software, and there both evaluate to same result as expected:

In Maple, I found that by removing the sqrt(2) from inside the tanh, then limit now works

e:=-tanh((a*x+b));
limit(e,x=0)

Is this a bug?

why dsolve gives division by zero on thi...

nm 11643 Maple 2024
ode dsolve differential-equations
August 05 2024
1 5

I do not have earlier Maple version to check now. But Maple 2024.1 gives division by zero on this second order ode with missing x. This looks like new problem in Maple. Would someone who have access to earlier version of Maple be able to check if this problem shows there also? I solved this and get y=x+3 as solution which Maple verifies.

> 

interface(version);

`Standard Worksheet Interface, Maple 2024.1, Windows 10, June 25 2024 Build ID 1835466`

> 

restart;
> 

ode:=diff(y(x),x$2)=(diff(y(x),x))^3-(diff(y(x),x))^2;
IC:=y(0)=3,D(y)(0)=1;

diff(diff(y(x), x), x) = (diff(y(x), x))^3-(diff(y(x), x))^2

y(0) = 3, (D(y))(0) = 1

> 

dsolve([ode,IC])

Error, (in dsolve) numeric exception: division by zero

> 

sol:=y(x)=3+x;
odetest(sol,[ode,IC])

y(x) = 3+x

[0, 0, 0]

> 

DEtools:-odeadvisor(ode);

[[_2nd_order, _missing_x], [_2nd_order, _reducible, _mu_y_y1]]

> 

infolevel[dsolve]:=5;

5

> 

dsolve([ode,IC])

Methods for second order ODEs:

--- Trying classification methods ---

trying 2nd order Liouville

trying 2nd order WeierstrassP

trying 2nd order JacobiSN

differential order: 2; trying a linearization to 3rd order

--- trying a change of variables {x -> y(x), y(x) -> x}

differential order: 2; trying a linearization to 3rd order

trying 2nd order ODE linearizable_by_differentiation

trying 2nd order, 2 integrating factors of the form mu(x,y)

trying differential order: 2; missing variables

-> Computing canonical coordinates for the symmetry [0, 1]

-> Rewriting ODE in canonical coordinates by means of differential invariants

Try computing 1 more symmetries for ODE written in canonical coordinates

 -> Computing symmetries using: way = 3

 Found another symmetry:

[1, 0]

 Found another symmetry:

[-x+y, 0]

Computing a convenient ordering to use the 3 symmetries available

<- differential order: 2; canonical coordinates successful

<- differential order 2; missing variables successful

Error, (in dsolve) numeric exception: division by zero

> 

dsolve(ode)

Methods for second order ODEs:

--- Trying classification methods ---

trying 2nd order Liouville

trying 2nd order WeierstrassP

trying 2nd order JacobiSN

differential order: 2; trying a linearization to 3rd order

--- trying a change of variables {x -> y(x), y(x) -> x}

differential order: 2; trying a linearization to 3rd order

trying 2nd order ODE linearizable_by_differentiation

trying 2nd order, 2 integrating factors of the form mu(x,y)

trying differential order: 2; missing variables

-> Computing canonical coordinates for the symmetry [0, 1]

-> Rewriting ODE in canonical coordinates by means of differential invariants

Try computing 1 more symmetries for ODE written in canonical coordinates

 -> Computing symmetries using: way = 3

 Found another symmetry:

[1, 0]

 Found another symmetry:

[-x+y, 0]

Computing a convenient ordering to use the 3 symmetries available

-> Calling odsolve with the ODE diff(_b(_a) _a) = _b(_a)^3-_b(_a)^2 _b(_a) HINT = [[1 0] [-_a+y -_b*(_b-1)]]

   *** Sublevel 2 ***

   symmetry methods on request

 1st order, trying reduction of order with given symmetries:

[1, 0], [-_a+y, -_b*(_b-1)]

   1st order, trying the canonical coordinates of the invariance group

   <- 1st order, canonical coordinates successful

<- differential order: 2; canonical coordinates successful

<- differential order 2; missing variables successful

y(x) = ln(LambertW(-c__1*exp(x-1)))+c__2

 

 

Download divide_by_zero_maple_2024_1_august_5_2024.mw

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