Entraides et échanges autour de la technologie Scol - Informations and exchanges on the Scol technology
Vous pouvez changer la langue de l'interface une fois inscrit - You can change the language once registered
You are not logged in.
Edited to reflect Iri's observation below, although I'm still having problems with formatting indents from bluefish.
There is probably a list function that would make this easier, but, in any case, if you have a struct of whatever kind, and one of the fields of the struct, named Iwhateverindex is an interger, and you are trying to find the object that has the highest Iwhateverindex , this is how you can do it. in this example, the Iwhateverindex property is named Icylinderindex:
struct Cylinder =[
Icylindernumber: I,
Icylinderindex: I,
Fradius : F,
Fheight : F,
Tlifespan : Timer,
Sbirthfphrase : S,
Sdeathphrase : S,
fundyingclyinder: fun [Cylinder] S,
funreturnarea : fun [Cylinder] F,
funreturnvolume: fun[Cylinder] F
]mkCylinder;;
typeof lCylinderlist=[Cylinder r1];;
typeof lDeleted_cylinder_ids= [I r1];;
typeof ICylinder_counter= I;;
var Ihighest_Cylinder_Index= 0;;
fun get_highest_id_from_cylinderlist (cylinderlist, id)=
//we want to get the highest Cylinder.Icylinderindex that exists in this list!!!!!
if ((hd cylinderlist)==nil)&& ((sizelist lCylinderlist)==0) then
(
_fooS "there are no items in the list at all";
1;
)
else if ((hd cylinderlist)==nil)&& ((sizelist lCylinderlist)>0) then
(
_fooS "we are at the end of a list that has items in it";
_fooS strcat "the following value is the highest value found in the complete list is: " (itoa id);
id;
)
else
//we are not at the end of the list yet
(
_fooS "there are items in the list and we are not at the end yet";
let hd cylinderlist -> cylinder in
let cylinder.Icylinderindex -> this_index in
if (this_index > id) then
(
set id = this_index;
_fooS strcat "the highest id found so far is: " (itoa id);
//we havve the higghest id so far, recursively search through rest of list
//to see if we can find a higher id
get_highest_id_from_cylinderlist (tl cylinderlist) id;
)
else
(
//don't change the id, we have the highest found so far
//so we recursively search through rest of list
_fooS strcat "the highest id found so far is: " (itoa id);
get_highest_id_from_cylinderlist (tl cylinderlist) id;
);
);;
fun main()=
_showconsole;
let mkCylinder [1 879 nil nil nil nil nil nil nil nil]-> cylinder1 in
let mkCylinder [2 1056 nil nil nil nil nil nil nil nil]-> cylinder2 in
let mkCylinder [3 3456 nil nil nil nil nil nil nil nil]-> cylinder3 in
set lCylinderlist = cylinder1:: cylinder2::cylinder3::lCylinderlist;
let nth_list lCylinderlist 0-> dcylinder in
let dcylinder.Icylinderindex -> index in
_fooS strcatn "the result of the index search through the list is: ":: (itoa (get_highest_id_from_cylinderlist lCylinderlist nil))::nil;;Last edited by hebdemnobad (30-Nov-2015 14:49:00)
Offline
there is no magic way
parse all the list and get the max index found
let 0 -> maxid in
set maxid = max curid maxid;
of use sort functions in the lib to sort the list by id and get the first element.
All this possibilities take a lot of time on big lists
Offline
Your function is incorrect.
Try with this main function (i added a 4th cylinder with a shorter index) :
fun main()=
_showconsole;
let mkCylinder [1 879 nil nil nil nil nil nil nil nil]-> cylinder1 in
let mkCylinder [2 1056 nil nil nil nil nil nil nil nil]-> cylinder2 in
let mkCylinder [3 3456 nil nil nil nil nil nil nil nil]-> cylinder3 in
let mkCylinder [4 2010 nil nil nil nil nil nil nil nil]-> cylinder4 in // <- added !
set lCylinderlist = cylinder1:: cylinder2::cylinder3::cylinder4::lCylinderlist;
let nth_list lCylinderlist 0-> dcylinder in
let dcylinder.Icylinderindex -> index in
_fooS strcatn "the result of the index search through the list is: ":: (itoa (get_highest_id_from_cylinderlist lCylinderlist nil))::nil;;The output is :
there are items in the list and we are not at the end yet
the highest id found so far is: 879
there are items in the list and we are not at the end yet
the highest id found so far is: 1056
there are items in the list and we are not at the end yet
the highest id found so far is: 3456
there are items in the list and we are not at the end yet
the result of the index search through the list is: 00 ? Really ?
Try with this easier function :
fun get_highest_id_from_cylinderlist (cylinderlist, id)=
if cylinderlist == nil then
(
_fooS "there are no items in the list at all";
id
)
else
let hd cylinderlist -> cylinder in
if cylinder.Icylinderindex > id then
(
_fooS strcat "the highest id found so far is: " itoa cylinder.Icylinderindex;
get_highest_id_from_cylinderlist tl cylinderlist cylinder.Icylinderindex
)
else
(
_fooS strcat "the current id is not greater than : " itoa id;
get_highest_id_from_cylinderlist tl cylinderlist id
);;The output should be :
the highest id found so far is: 879
the highest id found so far is: 1056
the highest id found so far is: 3456
the current id is not greater than : 3456
there are no items in the list at all
the result of the index search through the list is: 34563456 seems correct.
As Arkeon suggests, you may use the max function.
You may also define a global variable to store the max value. When a new cylinder is created, you compare its index with this variable. If it is bigger, you replace it.
Something like that :
typeof maxCylinderId;;
...
fun cylinderNew (arg, id, ....)=
let mkCylinder [... id ...] -> cylinder in
(
if id > maxCylinderId then
set maxCylinderId = id;
cylinder
);;to avoid to read the entire list each time.
PS : please, indent your code !!
Offline
in your text editor software change the tabulation setting to use 2 space character instead of tabulation
so the code is easier to copy / past.
Offline
Thanks for the correction Iri .....bluefish indents fone for me but I lose the tabs when I paste into posts. I will try changing that setting Arkeon.
[edit] I checked out my code....I hadn't pasted all of it in and it looks more or like your correct function Iri.
But I get the point...if you can avoid stepping through a list, especially a big one, it's better to do that.
Last edited by hebdemnobad (30-Nov-2015 13:01:44)
Offline