Am 23.12.2012 um 02:58 schrieb Roland Thiers
<roland.thi...@gmail.com>:
Bonjour,
I am new in ConTeXt. I love its features. I need some (or a lot of)
help.
I tried to get a macro which compute some values for a math function.
Le 23 déc. 12 à 18:43, Wolfgang Schuster a écrit :
\startluacode
userdata = userdata or {}
userdata.roland = userdata.roland or {}
local roland = userdata.roland
function roland.f(x)
context(x*x*x)
end
function roland.table(min,max,step)
local min = tonumber(min)
local max = tonumber(max)
local step = tonumber(step)
context.starttable({string.format("|*{%d}{l|}",max-min+2)})
context.HL()
context.VL()
context("x")
for i=min,max do
context.NC()
context(min+(i-1)*step)
end
context.VL()
context.FR()
context.HL()
context.VL()
context("f(x)")
for i=min,max do
context.NC()
roland.f(min+(i-1)*step)
end
context.VL()
context.AR()
context.HL()
context.stoptable()
end
\stopluacode
\define[3]\TableFuntion
{\ctxlua{userdata.roland.table("#1","#2","#3")}}
\starttext
\TableFuntion{1}{6}{1}
\TableFuntion{2}{7}{1}
\stoptext
Wolfgang
I read with care (maybe) your code above, Wolfgang (thanks again !) et
had a look in "programming in lua" to get a better idea of the object
table, new in lua too :-)
I have some more questions :
- when one create a table doing this : userdata=userdata or {}, is it
only to be sure that "userdata" is not actually a variable which
exists (with
a non nil value) ? Less safely we could write : userdata={} ?
- arguments for the user.data.table function are given as strings : "
#1" and changed in numbers in the body of the function. I noticed that
it was possible to
give numbers directly. is there always better to do like this ? (enter
strings et use tonumber)
- I found the command \define in context garden and saw it's the same
than \unexpanded\def , there is a link to the définitions of the TeX
primitives but
I could'nt find \unexpanded\def (\def was very instructive however).
- I changed slightly the code to obtain a range (x between min and max
with a step) and to choose a round-way.
I failed to find a context way to get rounded numbers, so I did a
workaround (a another function) with help from "programming in lua". I
would like a more straight (context) way.
Here is the code :
\startluacode
-- userdata = userdata or {}
-- userdata["roland"] = userdata["roland"] or {}
userdata=userdata or {}
userdata["roland"]=userdata["roland"] or {}
local roland = userdata["roland"]
function roland.f(x)
return math.log(x)
end
function roland.round (number, approx)
local power = 10^(approx or 0)
context(math.floor(number * power + 0.5) / power)
end
function roland.table(min,max,step,approx)
local min = tonumber(min)
local max = tonumber(max)
local step = tonumber(step)
local nbrcol = tonumber((max-min)*(1/step)+2)
local approx = tonumber(approx)
context.starttable({string.format("|*{%d}{l|}",nbrcol)})
context.HL()
context.VL()
context("x")
for i=1,(nbrcol-1) do
context.NC()
context(min+(i-1)*step)
end
context.VL()
context.FR()
context.HL()
context.VL()
context("f(x)")
for i=1,(nbrcol-1) do
context.NC()
local result=roland.f(min+(i-1)*step)
roland.round(result,approx)
end
context.VL()
context.AR()
context.HL()
context.stoptable()
end
\stopluacode
\define[4]\TableFuntion
{\ctxlua{userdata.roland.table("#1","#2","#3","#4")}}
\starttext
\TableFuntion{2}{6}{0.5}{2}
\blank[2*big]
\TableFuntion{1}{16}{1}{}
\blank[2*big]
\TableFuntion{2}{4}{2}{5}
\blank[2*big]
\TableFuntion{0.2}{2}{0.2}{3}
\stoptext
Best regards, Roland
Happy Christmas to all Context users !
___________________________________________________________________________________
If your question is of interest to others as well, please add an
entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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wiki : http://contextgarden.net
___________________________________________________________________________________
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl / http://tex.aanhet.net
archive : http://foundry.supelec.fr/projects/contextrev/
wiki : http://contextgarden.net
___________________________________________________________________________________
