Evaluate numerically trigonometric functions?

Questions
1

SpecificQuestion (V11) How to force numerical evaluation of trig functions?
I have tried multiple variants of below process ( only showing first output of loop
The process stops with the conversion of the degree to radians
Feeding the angle in as numeric didn’t change the outcome

N[N[expr,10],10]

doesn’t produce numeric output
Adding the second list and trying to apply N across the list also fails
If I copy one single sub expression from the output to a separate cell
it is not truncated to 10 digits cos[0.62831853071795864769252867665590057686`10.
it will still not evaluate with “N”
if manually truncated it will finally produce a numerical result

General Questions ,
does N force numeric evaluation up through all levels of a compound expression?
does N pass through list element by element?

IN:

For[i=0, i<rws, i++;

magangle=N[(2*i)*(360/rws),10];

Print[magangle];

magvec={N[cos[magangle Degree],10],N[sin[magangle Degree],10],0};

magveceval=N[magvec,10];

Print[magvec];

Print[magveceval]]

Out;

36.00000000

{cos[0.6283185307],sin[0.6283185307],0}

{cos[0.6283185307],sin[0.6283185307],0}
2

Mathematica is fiercely case sensitive.

rws = 10;
For[i = 0, i < rws, i++,
 magangle = N[(2*i)*(360 Degree/rws), 10];
 Print[magangle];
 magvec = {Cos[magangle], Sin[magangle], 0};
 Print[magvec];
 ]
3

Thank you

I am working simultaneously with 4 programs

a 2d finite element program
interfaced for scripting in Matlab/Octave

and a 3d counterpart

whose exclusive interface is Mathmatica

Switching back and forth is proving to be a nightmare due to simple things like this.
The syntax variations can become invisible,since they aren’t wrong on the "other side ".

Has anyone produced a comparison chart with common function and syntax comparisons and /or pitfalls?

Besides initial letter in CAPS and SQUARE brackets for functions :slight_smile: