It used to be that when I clicked on the little icon in the help window which tells Maple to display all examples in 1D, then I did not see any 2D or any document style (i.e. italic) notation in the examples.

Now in Maple 2017 I see many examples in help show up in 2D/italic. It is worst, on same page, some code displays in Maple language and some code displays in 2D notation.

I do not like 2D. I want to only see examples written in the plain good old fashioned Maple language (which Maplesoft seems to be trying very hard to kill as it seems to be trying to force document style/2D on users by any means).

Here is an example. ?diff shows this

The above has 2D as input and above it has Maple code as input. One can't even copy the input to the open worksheet. If I copy it, this what happens:

value(??);

Here is another example, from page titled

Scrolling down I see this

I want all the input code above in examples and documentation to be in plain 1D Maple language notation. Not italic and not 2D and not anything fancy.  I do not like to even look at italic code above.

But clicking on the icon has no effect.

Is there a way to force everything to show using Maple notation for input? 

Maple help and documenation is a big mess if you ask me.

Maple newbie here.

I do not understand why algsubs do not replace the symbol in the denominator in the following example, but does replace it in the numerator. This is on Maple 2017 on windows 7

Here is the expression

sol := u(x, t) = Sum((2*cos((1/2)*Pi*_Z1)+
       2+4*(-1)^(1+_Z1))*sin(Pi*_Z1*x/L)*
       exp(-k*Pi^2*_Z1^2*t/L^2)/(Pi*_Z1), 
       _Z1 = 1 .. infinity);

I wanted to replace _Z1  with n

But algsubs will not replace _Z1 in the denominator as seen in this screen shot but subs does:

From help, my impression is that algsubs is superset of subs. Only case where algsubs will not do what subs does is, according to help:

But There is no indexed names here? 

Can someone please explain why algsubs fails to do the substitution in the denominator in this example?

UPDATE

Thanks for checking. I verify I get the error and made screen shots below

When I add the convert() command, the error goes away. Here is screen shot

I am using Maple 2017, student version, on windows 7, 64 bit, home edition.

Original post

This is using Maple 2017 on windows.

With the following input, Maple pdsolve gives an error

pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=D[1](u)(0,t)=0,D[1](u)(L,t)=0:
assume(L>0):
ic:=u(x,0)=piecewise(0<x and x<=L/2,0,L/2<x and x<L,1):
sol:=pdsolve([pde,bc,ic],u(x,t)):

However, if I add one line to convert the piecewise function above to piecewise, then pdsolve no longer gives an error. So the following input works

restart;
pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=D[1](u)(0,t)=0,D[1](u)(L,t)=0:
assume(L>0):
ic:=u(x,0)=piecewise(0<x and x<=L/2,0,L/2<x and x<L,1):
ic:=convert(ic,piecewise,x):
sol:=pdsolve([pde,bc,ic],u(x,t)):

Notice the extra line. Why does one have to convert piecewise to piecewise to make pdsolve accept the input?

sorry did not write down the error message and I am writing this from school library PC. But if you try the first case, you'll see the error.

I have an update below

I am student, and bought Maple student version 2017 and went through verification and activation with no probems and been using Maple for number of days.

But few days ago, I disconnected my internet service provider, and so now I have no access to the internet from my home PC where I installed Maple (I am writing this from  library)

Now at home, when I start Maple, I get a message saying that my licence will expire in 10 or 9  days or so. I do not understand this messge. Why it comes up now and did not come up before when I had internet access? 

Does one need to be connected to the internet all the time to use Maple? What if one does not have internet access?

I did remove one monitor from my PC also. Do you think Maple detected change in PC (one less monitor) and now it thinks this is new PC? But this makes no sense.

How do I tell Maple I have activated my Maple if I do not have internet access?

Update

After installing Maple 2017.1, now each time I disconnect from the internet, I am not able to start Maple !  I get this error

When I connect to the internet and try again, Maple comes up OK and it works. (it does NOT ask me to activate). I have allready activated OK before. This message only comes up when I am not connected to the internet.

This tells me Maple is trying to connect to the internet each time for some reason to verify my installation? But when if I do not want to be connected to the internet and still use Maple?

I never installed beta Maple or anything like this before. What to do to make Maple start without being connected to the internet? I did not change my PC.

I am trying Maple 2017 pdsolve for heat PDE in 1D. It seems Maple can solve now  heat PDE with homogeneous dirichlet boundary conditions (good). But when I set the boundary conditions to homogeneous neumann B.C. instead, I get an answer when this B.C. is prescribed to the left side. When this B.C. is on the right side, I get an error. Which is strange.

I am newbie in Maple, so may be I am doing something wrong in the syntax?  In addition, the answer I get when homogeneous neumann B.C. is on the left side, does not match my hand solution, which I know is correct. I'll show this below.

First, here is the case where it works. homogeneous dirichlet boundary conditions on both sides:

restart;
pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=u(0,t)=0,u(L,t)=0;
sol:=pdsolve([pde,bc]) assuming 0<L:

This answer is correct. Now when setting the right side to homogeneous neumann B.C. I get an error

restart;
pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=u(0,t)=0,D[1](u)(L,t)=0;
pdsolve([pde,bc]) assuming 0<L;

I think may be it does not like `L` there in the B.C. But how else to tell it this B.C.? The above is the only syntax I know. And finally, when using homogeneous neumann B.C. on the left side, I get this result

restart;
pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=D[1](u)(0,t)=0,u(L,t)=0;
pdsolve([pde,bc]) assuming 0<L;

The correct answer for this B.C. is

The answer should be series solution as well with eigenvalues. I think if I expand Maple solution in series may be I will get it to match my hand solution. I need to look at this more later.

my question is: Why do I get an error when homogeneous neumann B.C. is on the right side but not on the left side?

I suspect I am not entering the B.C. correctly? If so, How does one enter homogeneous neumann B.C. for this 1D heat PDE?