List to Integer Not Working As Expected

[Selphie Wirefly]

I've striped this down to basically the bare bones of my issue  The resulting integer, next_x, is used elsewhere in the complete script, the llSay aspect just exists for troubleshooting.

The expected action here, when touched, the Prim will say the same number (picked from x_range) twice.

Instead what happens is the first llSay (string)next_x, always says 0, while the second, with the llList2String, works as expected.

I'm not sure what I'm doing wrong here and it feels like a simple issue.

list x_range = [-.5, 0, .5, 0];
integer counter;
 
default
{
    touch_start(integer total_number)
    {
    integer next_x=(integer)llList2String(x_range,counter);
    llSay(0,(string)next_x);
    llSay(0,llList2String(x_range,counter));
    counter++;
    }
}

 

[Rolig Loon]

The variables in your list are stored as floats.  You are trying to extract them as strings and typecast them to integers.

[Quistess Alpha]

when you defined x_range you did it using floats, so you need to pull them out of the list as floats using  llList2Float. perhaps you should do a review of the basic data types: http://wiki.secondlife.com/wiki/Category:LSL_Types

[Selphie Wirefly]

That makes sense, thanks.

[Mollymews]

sometimes using llList2String and then casting it the wanted type can be useful

like integer n = (integer)llList2String(x_range, 0)

we often need to do this when a list is filled from a notecard, as notecard lines are read/retrieved as strings

[Wulfie Reanimator]

Technically, the (integer)llList2String is kind of working. (By that I mean it could be considered "correct" depending on what you want.)

The values returned by List2String are something like "0.00000" and "0.50000" and then you cast them to integers, which throws out the ".00000" part and you're left with the whole number 0. You can see what I mean if you try a value like 1.5 or 253.0.

But yeah, if you want fractional values, you need llList2Float or just llList2String without anything extra.

[Selphie Wirefly]

12 hours ago, Wulfie Reanimator said:

Technically, the (integer)llList2String is kind of working. (By that I mean it could be considered "correct" depending on what you want.)

The values returned by List2String are something like "0.00000" and "0.50000" and then you cast them to integers, which throws out the ".00000" part and you're left with the whole number 0. You can see what I mean if you try a value like 1.5 or 253.0.

But yeah, if you want fractional values, you need llList2Float or just llList2String without anything extra.

 

You know in hind site, casting a .5 to int really was an obvious problem. 

In the larger script, I am using the list to control regular movement positions.  The adjustments being made will loop through the list and move a prim around as needed along one axis on a timer.

[Mollymews]

adding to the conversation

when we want regular partitioning (of the result of some calculation that can be irregular) then llRound() is useful

example rounding to tenths

float f = 2.152
f = llRound(f * 10.0) / 10.0
f * 10.0 = 21.52
llRound(f) = 22
22 / 10.0 = 2.2

float f = 2.148
f = llRound(f * 10.0) / 10.0;
f * 10.0 = 21.48
llRound(f) = 21
21 / 10.0 = 2.1

Edited March 25, 2021 by Mollymews