Page 1 of 3
naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 10:53 am
by wimapon
Hi folks,
after a long time with no problems with purebasic i encounterd a naugty problem.
i made a program for drawing contour lines within a grid of 100 grid nodes.
if i draw one line, say line of 80, all is okay.
But when i add: for contourline = 80 to 81 the program gives with both lines some fautly values.
When i after that remove the for contour line... this one line for 80 gives the same faulty values....
You should say, the program is exactly the same as in the beginning.
I think this must be a purebasic program.
It is a large program, so its is better not to give it here.
Thanks for your help
Wim Apon
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:01 am
by wimapon
sorry, i will say: this must be a pure basic problem.
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:03 am
by wimapon
restarting the computer of restarting purebasic, and even run this progam on a other computer gives the same problem...
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:06 am
by STARGÅTE
I don't understand your description. (limitation of your english?)
Where is the coding question?
Edit: You can edit your post, no need for adding two additional posts.
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:16 am
by BarryG
wimapon wrote: Fri Feb 25, 2022 10:53 amI think this must be a purebasic program
If you mean "bug" instead of "program", then I doubt it is. Try to make a small snippet showing the problem.
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:26 am
by wimapon
![Image]()
sorry about my english: it is a difficult problem to explain.
i can show 3 .jpg files to demonstrate the results.....
but for me this is a new layout for the forum.
i can not find how to post a picture, and how to edit my text\
i will give it a try i can't
![Image]()
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:53 am
by STARGÅTE
wimapon wrote: Fri Feb 25, 2022 11:26 am
i can not find how to post a picture, and how to edit my text\
Picture can be embedded with [
img] URL of the image [/
img].
However, the picture have to be uploaded on a third party website.
You can edit your post, when you click on the pencil icon next to this post.
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 11:59 am
by wimapon
Demonstration of my problem:
The grid nodes are measuring points of a continuous surface.
so my program draws lines of points with the same value. ( contour lines)
in this example the contourline of 80
first picture is only the 80 m contourline
the second picture is the same program with a extra for next line , so you get the contourlines 80 and 81
then i delete the for next line and you get the third picture.
the program is now exactly the same as for the first picture.
So what is happening.... ???
i made all used variables to zero for the next -- for next loop --
please forget the labels at the x and y axis
the grid nodes has more decimals than shown.
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 12:50 pm
by STARGÅTE
Thanks for the pictures, but without any code example we can not help you.
For me it looks like, array elements or list elements are overwritten during the change of the contour line.
Because no code is given, here are general remarks:
- Do you use EnableExplicit?
- Do you use Threads?
- What happens, when you enable the debugger and the purifier?
- Are always the same points and same contour lines showing this issue?
- Are the array sizes correct?
- Do you use lists in multiple procedures?
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 1:09 pm
by wimapon
Hi Stargate,
I made this program in 1987 in quick basic.
Now i translated it to purebasic.
I do not use special purebasic features. no threats, no stuctures, no purifier.
i start the program and go line for line down to the end.
grid sizes are correct.
i use only one subroutine which translate real coordinates to screen coordinates.
i can give the source of the contouring algoritme , but is is 300 lines...
if you wish i can delete all comments and debug lines.... then it will be something like 100 lines
so ??
Wim
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 1:10 pm
by BarryG
wimapon wrote: Fri Feb 25, 2022 1:09 pmi can give the source of the contouring algoritme , but is is 300 lines
300 lines is nothing. Post it, or even the whole code if it's not private/secret.
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 1:13 pm
by wimapon
Okay, i will post the contouring lines and delete most of the comments and debug lines.
this takes a while
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 1:45 pm
by wimapon
Code: Select all
; this is the part of the contouring program that calculates the contour lines.
; It has 2 for next loops.. one for horizontal and one for vertical
; this part of the program gives the third picture for the forum ( in the complete program)
; it compiles okay, but does nothing.
Declare Verschaal()
n = 11 ; aantal gridlijnen eerste=0
Dim w.d(n,n) ; grid-matrix eerste getal is langs de x-as tweede getal is langs de y-as
Dim puntx.d(40) ; snijpunten van een contourlijn met een gridvierkant
Dim punty.d(40)
; De minima en maxima van mijn grafiek in mijn coordinaten
Global Xmin.d = 0
Global Xmax.d = 100
Global Ymin.d = 0 ; -0.01
Global Ymax.d = 100 ; 0.01
Global x.d, y.d, xw.d, yw.d
Global Xoffset.d = 90 ; 70.0
Global Yoffset.d = 40.0
; $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
; $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
; ga nu een contourlijn door alle gridcellen tekenen
; For contourlijn = 80 To 81
contourlijn = 80
For j = 0 To 9
For i = 0 To 9
;Even alle variabelen weer op 0 zetten
For i2=0 To 4
puntx(i2)=0
punty(i2)=0
Next i2
tel=0 ;'t.b.v. het trekken van een contourlijn binnen een gridcel
;' Is het aantal keren dat een grid-cel-wand gesneden wordt
; snijdt de contourlijn de basis van de gridcel?
;================================================
antw$ = "n"
px.d = 0
py.d = 0
; doe iets als een waarde van een gridpunt precies hetzelfde is als de contourlijn
If contourlijn=w(i,j)
w(i,j)=w(i,j)+0.00001
EndIf
If contourlijn=w(i+1,j)
w(i+1,j)=w(i+1,j)+0.00002
EndIf
If contourlijn > w(i,j) And contourlijn < w(i+1,j)
antw$ = "j"
EndIf
If contourlijn < w(i,j) And contourlijn > w(i+1,j)
antw$ = "j"
EndIf
If antw$ = "j" ; de contourlijn cuts the base of the gridcell
; bereken het snijpunt.
afstand.d = (contourlijn-w(i,j) ) / (w(i+1,j) - w(i,j))
px = i + afstand
py = j
tel = tel + 1
puntx(tel) = px
punty(tel) = py
; plot dit punt
x = puntx(tel)
y = punty(tel)
verschaal()
Circle(xw,yw,5,RGB(255,255,0)) ; geel
EndIf
; snijdt de contourlijn de linkerzijde van de gridcel?
;================================================
antw$ = "n"
px.d = 0
py.d = 0
If contourlijn=w(i,j)
w(i,j)=w(i,j)+0.00007
EndIf
If contourlijn=w(i,j+1)
w(i,j+1)=w(i,j+1)+0.00008
EndIf
If contourlijn > w(i,j) And contourlijn < w(i,j+1)
antw$ = "j"
EndIf
If contourlijn < w(i,j) And contourlijn > w(i,j+1)
antw$ = "j"
EndIf
If antw$ = "j" ; de contourlijn snijdt de linker zijde van de gridcel
; bereken het snijpunt.
afstand.d = (contourlijn-w(i,j) ) / (w(i,j+1) - w(i,j))
px = i
py = j + afstand
;Debug px
tel = tel + 1
puntx(tel) = px
punty(tel) = py
; plot dit punt
x = puntx(tel)
y = punty(tel)
verschaal()
Circle(xw,yw,5,RGB(0,0,255)) ; blauw
EndIf
; snijdt de contourlijn de bovenzijde van de gridcel?
;================================================
antw$ = "n"
px.d = 0
py.d = 0
If contourlijn=w(i,j+1)
w(i,j+1)=w(i,j+1)+0.00005
EndIf
If contourlijn=w(i+1,j+1)
w(i+1,j+1)=w(i+1,j+1)+0.00006
EndIf
If contourlijn > w(i,j+1) And contourlijn < w(i+1,j+1)
antw$ = "j"
EndIf
If contourlijn < w(i,j+1) And contourlijn > w(i+1,j+1)
antw$ = "j"
EndIf
If antw$ = "j" ; de contourlijn snijdt de bovenzijde van de gridcel
; bereken het snijpunt.
afstand.d = (contourlijn-w(i,j+1) ) / (w(i+1,j+1) - w(i,j+1))
px = i + afstand
py = j +1
tel = tel + 1
puntx(tel) = px
punty(tel) = py
; plot dit punt
x = puntx(tel)
y = punty(tel)
verschaal()
Circle(xw,yw,5,RGB(0,255,0)) ; groen
EndIf
; snijdt de contourlijn de rechter zijde van de gridcel?
;================================================
antw$ = "n"
px.d = 0
py.d = 0
If contourlijn=w(i+1,j)
w(i+1,j)=w(i+1,j)+0.00003
EndIf
If contourlijn=w(i+1,j+1)
w(i+1,j+1)=w(i+1,j+1)+0.00004
EndIf
If contourlijn > w(i+1,j) And contourlijn < w(i+1,j+1)
antw$ = "j"
EndIf
If contourlijn < w(i+1,j) And contourlijn > w(i+1,j+1) ; moet als de twee waarden omgekeerd in grootte zijn
antw$ = "j"
EndIf
; Debug antw$
If antw$ = "j" ; de contourlijn snijdt de rechterzijde van de gridcel
; bereken het snijpunt.
afstand.d = (contourlijn-w(i+1,j) ) / (w(i+1,j+1) - w(i+1,j))
px = i+1
py = j + afstand
tel = tel + 1
puntx(tel) = px
punty(tel) = py
; plot dit punt
x = puntx(tel)
y = punty(tel)
verschaal()
Circle(xw,yw,5,RGB(255,0,0)) ; rood
EndIf
; plot nu de lijnstukken
x = puntx(1)
y = punty(1)
verschaal()
xw1 = xw
yw1 = yw
x = puntx(2)
y = punty(2)
verschaal() ; input is x and y output = xw and yw
xw2 = xw
yw2 = yw
; LineXY(xw1,yw1,xw2,yw2,RGB(255,255,0)) ; this line will not compile because no drawing is defined.
; in the real program it is running okay
If puntx(4) <>0 ; there will be 2 lines going through this gridcell
x = puntx(3)
y = punty(3)
verschaal()
xw1 = xw
yw1 = yw
x = puntx(4)
y = punty(4)
verschaal()
xw2 = xw
yw2 = yw
; LineXY(xw1,yw1,xw2,yw2,RGB(255,255,0))
EndIf
Next i
Next j
; Next contourlijn
; $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
; $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
End
;
Procedure Verschaal()
;*====================*============================================***==============================*
;| Procedure Name ....| Verschaal
;| Description .......| changes real coordinates to screen coordinates
;| Syntax ............| Verschaal()
;| Parameter(s) ......| x y
;| Return value ......| wx yw
;| Author(s) .........| Wimapon
;| Versions ..........| 0001:2010-12-31:Creation Date
;*--------------------*-----------------------------------------------------------------------------*
;| Remarks ...........|
;*====================*=============================================================================*
xw = (x-Xmin) / (Xmax-Xmin) * (ImageW - Xoffset) + Xoffset
yw = (ImageH - Yoffset) -( (y - Ymin) / (Ymax-Ymin) * (ImageH - Yoffset))
EndProcedure
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 1:47 pm
by wimapon
spaces are visible
Re: naugty problem with for next in grid calculations
Posted: Fri Feb 25, 2022 2:15 pm
by STARGÅTE
Please edit your post and add the [code] [/code] tags around the code.