Hi Pablo,
I printed the file at my high school yesterday and the output is not the one expected. I get a document in portrait format and the mathematical formulas overflow in the other column.
Fabrice

2017-10-16 20:53 GMT+02:00 Fabrice Couvreur <fabrice1.couvreur@gmail.com>:

Hi Pablo,
I'm not sure I understand but I'll test tomorrow in high school.
With the file below, using what you offer, will the dimensions of my page be respected ?

\setuplayout
   [header=\zeropoint,
    headerdistance=\lineheight,
    backspace=2cm,
    width=middle,
    topspace=\dimexpr 2cm-\headerheight-\headerdistance\relax,
    footer=\lineheight,
    height=middle]

\setupinteractionscreen[option=landscape]  

\setuppagenumbering[alternative=,location=]

\definemixedcolumns
  [MyColumns]
  [
    n=2,
    separator=rule,
    rulecolor=,
    balance=yes,
  ]

\setupalign[verytolerant,stretch,hanging]

\starttext
\startMyColumns
\startformula
    \startmathalignment[n=2,align={left,left}] 
    \NC P_1 + P_2 + \dots + P_{12} \NC = 400 + 400\times 1,05 + 400\times 1,05^2 + \dots + 400 \times 1,05^{11}\NR
    \NC  \NC = 400\times (1 + 1,05 + 1,05^2 + \dots + 1,05^{11})\NR
    \NC  \NC = 400\times \frac{1-1,05^{12}}{1-1,05}\approx 6\,367.\NR
    \stopmathalignment 
  \stopformula 
\dorecurse{6}{\input knuth}
\stopMyColumns
\stoptext

2017-10-16 19:35 GMT+02:00 Pablo Rodriguez <oinos@gmx.es>:

On 10/16/2017 05:59 PM, Fabrice Couvreur wrote:
> Hello,
> I have printed this document and the page on the back is printed upside down
> in fact you have to turn the page to read it.
> How to correct this ?
> Thank you
> Fabrice
>
> \setuppapersize[A4,landscape]

Hi Fabrice,

[the command above is the only relevant one, lanscape page orientation.]

If you use a recent version of Acrobat, you may use:

   \setupinteractionscreen[option=landscape]

This will automatically print it in the right way. In that case, you
don’t have to select anything in Acrobat, the program will read it from
the PDF document itself.

If you use another viewer, select flip long edge of the paper.

Just in case it helps,

Pablo
--
http://www.ousia.tk
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