Difference between revisions of "ListXnotY"

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m (calling the llGetListLength function outside the for statement, saves time. Also there is only one case in the if statement)
m (<lsl> tag to <source>)
 
(12 intermediate revisions by 8 users not shown)
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{{LSL Header}} __NOTOC__
{{LSL Header}} __NOTOC__
[[Category:LSL_User-Defined Functions]]
<div id="box">
<div id="box">
== Function: [[list]] ListXnotY([[list]] {{LSL Param|lx}}, [[list]] {{LSL Param|ly}}); ==
== Function: [[list]] ListXnotY([[list]] {{LSL Param|lx}}, [[list]] {{LSL Param|ly}}); ==
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See also: [[List|Lists]]
See also: [[List|Lists]]


<lsl>
<source lang="lsl2">
list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
     list lz;
     list lz;
integer i;
    integer i = llGetListLength(lx);
integer n = llGetListLength(lx);
    while(i--)
for (i = 0; i < n; i++)
if ( !~llListFindList(ly,llList2List(lx,i,i)) ) // * see Note
{
             lz += llList2List(lx,i,i);
        if (llListFindList(ly,llList2List(lx,i,i)) == -1)
             lz = lz + llList2List(lx,i,i);
    }
     return lz;
     return lz;
}
}


</lsl>
</source>
 
Note: If the if test is written as '''if (!~llListFindList''' ... , the result will be a list of elements in X that are ''missing'' from list Y. If it is written as '''if (~llListFindList''' ... , the result will be a list of elements in X that are ''present'' in list Y.


Example:<br />
Example:<br />


<lsl>
<source lang="lsl2">
list l1 = ["a","b","c","d"];
list l1 = ["a","b","c","d"];
list l2 = ["a","1","b","2","c","3"];
list l2 = ["a","1","b","2","c","3"];
list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
    list lz;
    integer i = llGetListLength(lx);
    while(i--)
if ( !~llListFindList(ly,llList2List(lx,i,i)) )
            lz += llList2List(lx,i,i);
    return lz;
}


default{
default{
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   }
   }
}
}
</lsl>
</source>


</div>
</div>


Posted with the kind permission of Very Keynes, who originated this script June 2007 in the SL scripters forum http://forums.secondlife.com/showthread.php?t=194138
Posted with the kind permission of Very Keynes, who originated this script June 2007 in the SL scripters forum http://forums-archive.secondlife.com/54/e4/194138/1.html


{{LSLC|Examples|ListXnotY}}
{{LSLC|Examples|ListXnotY}}

Latest revision as of 14:25, 22 January 2015

Function: list ListXnotY(list lx, list ly);

Show what x list has that y list is missing.

See also: Lists

list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
    list lz;
    integer i = llGetListLength(lx);
    while(i--)
	if ( !~llListFindList(ly,llList2List(lx,i,i)) )  // * see Note
            lz += llList2List(lx,i,i);
    return lz;
}

Note: If the if test is written as if (!~llListFindList ... , the result will be a list of elements in X that are missing from list Y. If it is written as if (~llListFindList ... , the result will be a list of elements in X that are present in list Y.

Example:

list l1 = ["a","b","c","d"];
list l2 = ["a","1","b","2","c","3"];

list ListXnotY(list lx, list ly) {// return elements in X list that are not in Y list
    list lz;
    integer i = llGetListLength(lx);
    while(i--)
	if ( !~llListFindList(ly,llList2List(lx,i,i)) )
            lz += llList2List(lx,i,i);
    return lz;
}

default{
   state_entry() {
      llSay(0, "X list has this in it, but Y list doesn't: " + llList2CSV(ListXnotY(l1,l2)) );
      //will say: d
   }
}

Posted with the kind permission of Very Keynes, who originated this script June 2007 in the SL scripters forum http://forums-archive.secondlife.com/54/e4/194138/1.html