@acer 

Thanks

Yes, i add a pointplot and extent the array ,but forget to adjust p[0] into p[0,1] 

I took a working procedure from you with maplemint no errors and then with my not working procedure with maple mint with errors and compare.

Its the first time i add quotes ...(could it be that i took old original code from example 2.3 again without quotes, that happened i think)   

That rng::range(numeric definition)  is not precisely explained how it works ..it is in Maple help ?

Evaluation rules the books give explanation about levels and the procedure variables are also different evaluated then in a interactive session.
a=b,b=c,c=d,d=16 is evaluated at   a=16 this is fourth level of evaluation in a interactive session as example.

@acer 

It was more difficult then i thought to make this procedure Tangentlines(f,a..b), but it is not working as intended.

betounes_ex_set_2_opg_6via_codeexample2.3_uitwerking.mw

@janhardo 

@acer : I leave it to you to add the interval as an additional parameter for your procedures.

You made a procedure out of task (exc set 2 task 3: drawing 6 tangentlines in the inflection points of  f ). 
Now there must be made a procedure from a code example 2.3 (tangentlines at maxs or mins) in book , that was the do task.
But it is now drawing tangentlines for a interval divided in 5 sub intervals with a procedure. 

betounes_ex_set_2_opg_6via_codeexample2.3.mw

I am working on it.

maplemint(Tangentlines);
Procedure Tangentlines( f )
  These names were used as global names but were not declared:  black, color,
      thickness, x
  Ineffectual call to with() inside a proc at statement 10: with(plots)

@acer: I suggest that you also add the name x as a local to your procedure, if you intend to continue to utilize it as a dummy name therein. Otherwise your procedure will not work if the name x has been assigned, say, a numeric value at the higher level.

Can you give a example with the procedure ? 
 

@janhardo 

Don't know how to make from this factorial function suitable for set and list elements

Factorial:= (n::nonnegint)-> local r:= 1, k:= 0; do r*= ++k until k>=n;

-------------------------------------------------------------------
PR:=proc(A,N)   # PR is product
   p:=1;
   for i from 1 to N do p:=p*A[i] end do:
end proc;

A is a list or set or array

example:

@janhardo 

I am looking now at the factorial definition :

Factorial:= (n::nonnegint)-> local r:= 1, k:= 0; do r*= ++k until k>=n;

or as 2D math input makes a big difference in reading!

for example: n::nonnegint is n element of set Z with 0 and positve numbers elements: 2D is showing the symbol notation 

Is it possible to outcomment 2D math too as with Maple input : # and /*..*/

@Carl Love 

An alternative formulation is

SumList:= (L::list(algebraic))-> 
    if L=[] then 0 else local S:= 0, x; for x in L do S:= S+x od fi
:

This is not looking here above anymore on a procedure definition with proc().. end proc;? 
But it seems to be a procedure. 
Its function made by the operator -> then.

Another point about a while clause of the do statement in relation to summing up a list of numbers 

I can take a partial sum of the list,therefore should be needed a while clause  

@acer 

Thanks

Amazing the root finding. 
After such a long time after 2002 (book),  i  could aspect  that fsolve is surpassed by other rootfinding methods  ?

It's specialized knowledge:numeric rootfinding methods.
I can't  go further  in detail for all sort of functions to use in this procedure, right now that's why my attention goes to other things like maplemint.

@Carl Love

Thanks

Get now a good oversight of some loop types

I will study your examples more extensive in Maple   

@acer 

Thanks

Looks great the procedure  when i fill in a function, but by the second one there is a error  message
Error, (in RootFinding:-NextZero) can only handle isolated zeros

It means that there will be limit in what sorts of functions i can enter in the procedure  
example :  sin(x)-x*cos(x)  ..ok and add tan(x) :  sin(x)-x*cos(x)+tan(x)-> error 

I study further with maplemint, because i don't now what rootfinding method to use further ? 

Try to make a procedure from two code examples what are doing the same.
Start first with only as procedure input a function, but that seems to be not working.
The procedure input must be a function , but the points where the tangentlines must occur inthe procedure is not understood. ( see task6 )

---------------------------------------------------------------------

Download betounes_ex_set_2_opg_6.mw

@Carl Love 

Thanks

Indeed i am struggling with the loops and try to improve this
Two forms of the do loop 
- for-from loop
- for -in loop

Your loopexample in the SumList procedure seems to be advanced ( don't know r+)
Tried making the factorial procedure, but make no progress yet.

Yes, the simpler loop example for the procedure SumList you mentioned, is for now easier to understand 
The capital S in the  do loop is a remainder that S is the last executed statement ?

@acer 

Thanks 

I found them back the worksheets from Roger Kraft about programming in Maple 

https://www.maplesoft.com/applications/view.aspx?SID=4744

@dharr 

Thanks

Cannot be shorter :)

@Axel Vogt 

Thanks 

Thereis not much to find about this in the book until now  

@Pascal4QM 

Thanks