[NTG-context] Re: Metapost limitation ?
Hi,
On Sun, May 12, 2024 at 6:24 PM Fabrice Couvreur <
fabrice1.couvr...@gmail.com> wrote:
>
> With Okular, it works !
Very good. You can still try the thing below:
\startluacode
local exp = math.exp
local N = 1000
local xstep = 1.6/N
local ystep = 1.8/N
local xmin = 0.3
local ymin = 0.4
local function f(x,y)
local x = xstep*x - xmin
local y = ystep*y - ymin
local z = x + exp(-60*x) - y
if z > 0 then
return '1'
else
return '0'
end
end
potrace.setbitmap("mybitmap", potrace.contourplot(N,N,f))
\stopluacode
\startMPpage[offset=1dk]
path p ; p := lmt_potraced [
stringname = "mybitmap",
value = "1",
tolerance = 0.1,
threshold = 0.2,
optimize = true,
] ;
p := p xsized 10cm ;
draw p withpen pencircle scaled 5 withcolor "darkblue" ;
drawpoints p withcolor "orange" ;
drawpointlabels p ;
p := subpath(6,19) of p ;
draw p withpen pencircle scaled 3 withcolor "yellow" ;
\stopMPpage
Another thing, Hans added nocycle, so you can write your loop if you want
to use it as something like
def compute_curve(suffix f)(expr xmin, xmax, xinc) =
for x=xmin step xinc until xmax:
(x,f(x)) ..
endfor nocycle ;
enddef;
Then you do not need to think about the first and/or last point separately.
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[NTG-context] Re: Metapost limitation ?
With Okular, it works ! Le dim. 12 mai 2024 à 17:55, Hans Hagen a écrit : > On 5/12/2024 5:36 PM, Fabrice Couvreur wrote: > > Sorry for the comment ! > > I use Evince > so how about okular or mupdf > > - >Hans Hagen | PRAGMA ADE >Ridderstraat 27 | 8061 GH Hasselt | The Netherlands > tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl > - > > > ___ > If your question is of interest to others as well, please add an entry to > the Wiki! > > maillist : ntg-context@ntg.nl / > https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl > webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror) > archive : https://github.com/contextgarden/context > wiki : https://wiki.contextgarden.net > > ___ > ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror) archive : https://github.com/contextgarden/context wiki : https://wiki.contextgarden.net ___
[NTG-context] Re: Metapost limitation ?
On 5/12/2024 5:36 PM, Fabrice Couvreur wrote: Sorry for the comment ! I use Evince so how about okular or mupdf - Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl - ___ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror) archive : https://github.com/contextgarden/context wiki : https://wiki.contextgarden.net ___
[NTG-context] Re: Metapost limitation ?
Sorry for the comment !
I use Evince
Le dim. 12 mai 2024 à 17:30, Hans Hagen a écrit :
> On 5/12/2024 3:57 PM, Fabrice Couvreur wrote:
> > Hi,
> > When I want to draw the curve which corresponds to n=60 (blue curve), it
> > doesn't seem possible: I don't understand.
> > Thanks
> > Fabrice
> >
> > \startMPpage[offset=1DK]
> >
> >numeric u;
> >u = 6cm;
> >
> >interim linejoin := mitered;
> >interim ahangle := 30;
> >
> >path xx, yy;
> >xx = ( (-0.3,0) -- 1.4 right) scaled u;
> >yy = ( (-0.1,0) -- 1.8 right) rotated 90 scaled u;
> >
> >def compute_curve(suffix f)(expr xmin, xmax, xinc) =
> >((xmin,f(xmin))
> >for x=xmin+xinc step xinc until xmax:
> > .. (x,f(x))
> >endfor)
> >enddef;
> >
> >
> >for i = 1 upto 4:
> >
> >vardef f(expr x) =x+exp(-i*x) enddef;
> >
> >path curve;
> >
> >curve = compute_curve(f,-0.4,1.4,0.0001) scaled u;
> >
> >draw curve;
> >
> >endfor;
> >
> >vardef f(expr x) =x+exp(-6*x) enddef;
> >
> >path curve;
> >
> >curve = compute_curve(f,-0.4,1.4,0.0001) scaled u;
> >
> >draw curve;
> >
> >vardef f(expr x) =x+exp(-15*x) enddef;
> >
> >path curve;
> >
> >curve = compute_curve(f,-0.4,1.4,0.0001) scaled u;
> >
> >draw curve;
> >
> >
> >vardef f(expr x) =x+exp(-60*x) enddef;
> >
> >path curve;
> >
> >curve = compute_curve(f,-0.4,1.4,0.0001) scaled u; -> not
> > drawn
>
> best put a comment before the ->>>
>
> >draw curve withcolor blue;
> >
> >
> >drawarrow (0,0) -- (u,0) withpen pencircle scaled 1.5bp;
> >drawarrow (0,0) -- (0,u) withpen pencircle scaled 1.5bp;
> >
> >
> >label.urt("A",(0,1u));
> >
> >draw xx;
> >draw yy;
> >
> >draw (1u,0) -- (1u,1.8u);
> >
> >
> >label.llft("0",(0,0));
> >
> > vardef mark_y_axis(expr value, name) =
> > save p; pair p; p = value * u * up;
> > draw (left--right) scaled 1 shifted p;
> > label.lft(name, p shifted 2 left);
> >enddef;
> >
> >for a = 1 upto 1:
> > mark_y_axis(a, "");
> >endfor
> >
> > mark_y_axis(1, "$1$");
> >
> >
> > vardef mark_x_axis(expr value, name) =
> > save p; pair p; p = value * u * right;
> > draw (up--down) scaled 1 shifted p;
> > label.bot(name, p shifted 2 down);
> > enddef;
> >
> > for a = 1 upto 1:
> > mark_x_axis(a, "");
> > endfor
> >
> > mark_x_axis(1, "$1$");
> >
> >
> >path rectangle;
> >rectangle = (-0.3u,-0.4u) -- (1.3u,-0.4u) -- (1.3u,-0.4u) --
> > (1.3u,1.4u) -- (-0.3u,1.4u)--cycle;
> >
> >clip currentpicture to rectangle;
> > \stopMPpage
> >
> your exp usage:
>
>exp(-60*-0.4)
>
> if you see what huge numbers come out of that, like
>
> -51.006602 11100558579.857309 l
> -50.989594 11034154639.123087 l
> -50.972586 10968147929.149401 l
> -50.955579 10902536073.687559 l
> -50.938571 10837316710.703716 l
>
> you could imagine a viewer crapping out on that because no matter what
> one clips it still is 'kind of drawn', so what viewer do you use?
>
> Hans
>
> -
>Hans Hagen | PRAGMA ADE
>Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
> tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
> -
>
>
> ___
> If your question is of interest to others as well, please add an entry to
> the Wiki!
>
> maillist : ntg-context@ntg.nl /
> https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
> webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
> archive : https://github.com/contextgarden/context
> wiki : https://wiki.contextgarden.net
>
> ___
>
___
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl /
https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
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archive : https://github.com/contextgarden/context
wiki : https://wiki.contextgarden.net
___
[NTG-context] Re: Metapost limitation ?
On 5/12/2024 3:57 PM, Fabrice Couvreur wrote:
Hi,
When I want to draw the curve which corresponds to n=60 (blue curve), it
doesn't seem possible: I don't understand.
Thanks
Fabrice
\startMPpage[offset=1DK]
numeric u;
u = 6cm;
interim linejoin := mitered;
interim ahangle := 30;
path xx, yy;
xx = ( (-0.3,0) -- 1.4 right) scaled u;
yy = ( (-0.1,0) -- 1.8 right) rotated 90 scaled u;
def compute_curve(suffix f)(expr xmin, xmax, xinc) =
((xmin,f(xmin))
for x=xmin+xinc step xinc until xmax:
.. (x,f(x))
endfor)
enddef;
for i = 1 upto 4:
vardef f(expr x) =x+exp(-i*x) enddef;
path curve;
curve = compute_curve(f,-0.4,1.4,0.0001) scaled u;
draw curve;
endfor;
vardef f(expr x) =x+exp(-6*x) enddef;
path curve;
curve = compute_curve(f,-0.4,1.4,0.0001) scaled u;
draw curve;
vardef f(expr x) =x+exp(-15*x) enddef;
path curve;
curve = compute_curve(f,-0.4,1.4,0.0001) scaled u;
draw curve;
vardef f(expr x) =x+exp(-60*x) enddef;
path curve;
curve = compute_curve(f,-0.4,1.4,0.0001) scaled u; -> not
drawn
best put a comment before the ->>>
draw curve withcolor blue;
drawarrow (0,0) -- (u,0) withpen pencircle scaled 1.5bp;
drawarrow (0,0) -- (0,u) withpen pencircle scaled 1.5bp;
label.urt("A",(0,1u));
draw xx;
draw yy;
draw (1u,0) -- (1u,1.8u);
label.llft("0",(0,0));
vardef mark_y_axis(expr value, name) =
save p; pair p; p = value * u * up;
draw (left--right) scaled 1 shifted p;
label.lft(name, p shifted 2 left);
enddef;
for a = 1 upto 1:
mark_y_axis(a, "");
endfor
mark_y_axis(1, "$1$");
vardef mark_x_axis(expr value, name) =
save p; pair p; p = value * u * right;
draw (up--down) scaled 1 shifted p;
label.bot(name, p shifted 2 down);
enddef;
for a = 1 upto 1:
mark_x_axis(a, "");
endfor
mark_x_axis(1, "$1$");
path rectangle;
rectangle = (-0.3u,-0.4u) -- (1.3u,-0.4u) -- (1.3u,-0.4u) --
(1.3u,1.4u) -- (-0.3u,1.4u)--cycle;
clip currentpicture to rectangle;
\stopMPpage
your exp usage:
exp(-60*-0.4)
if you see what huge numbers come out of that, like
-51.006602 11100558579.857309 l
-50.989594 11034154639.123087 l
-50.972586 10968147929.149401 l
-50.955579 10902536073.687559 l
-50.938571 10837316710.703716 l
you could imagine a viewer crapping out on that because no matter what
one clips it still is 'kind of drawn', so what viewer do you use?
Hans
-
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
___
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl /
https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive : https://github.com/contextgarden/context
wiki : https://wiki.contextgarden.net
___
