Google Charts

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This script allows you to take an existing list of values and represent it as a chart using Google's Chart API. The example here takes a list of visitors per hour and represents it as a bar chart. The simpleEncoding method provided by Google has been converted to LSL script.

Example

string simpleEncode(list values, float min, float max)
{
    string text = "";
    float range = 244 / (min - max);//4 * 61
    integer index = -llGetListLength(values);
 
    do
    {
        integer type = llGetListEntryType(values, index);
        if(type == TYPE_FLOAT || type == TYPE_INTEGER)
            text = llGetSubString(llIntegerToBase64((integer)(range * (min - llList2Float(values, index)))), 4, 4) + text;
        else
            text = "_" + text;
 
        ++index;
    }
    while (index);
 
    return text;
}
 
string cleanup(float value)
{
    string str = (string)value;
    if(value >= 10.0)
        return llGetSubString(str, 0, -8);
 
    integer i = -1;
    while(llGetSubString(str, i, i) == "0")
        --i;
 
    if(llGetSubString(str, i, i) == ".")
        --i;
 
    return llGetSubString(str, 0, i);
}
 
string chartUrl(list values, list captions, integer yDivisions)
{
    integer min = llFloor(llListStatistics(LIST_STAT_MIN, values));
    integer max = llCeil(llListStatistics(LIST_STAT_MAX, values));
 
    string url = "http://chart.apis.google.com/chart"
               + "?chs=200x125"
               + "&chd=s:" + simpleEncode(values, min, max)
               + "&cht=lc"
               + "&chxt=x,y"
               + "&chxl=0:";
 
    integer index = -llGetListLength(captions);
    do
    {
        url += "|" + llEscapeURL(llList2String(captions, index));
        ++index;
    }
    while (index);
 
    url += "|1:";
    ++yDivisions;
    float range = max - min;
 
    index = 1;
    do
    {
        url += "|" + cleanup(((index * range) / yDivisions) + min);
        ++index;
    }
    while (index <= yDivisions);
 
    return url;
}
 
default
{
    state_entry()
    {
        // PUBLIC_CHANNEL has the integer value 0
        llSay(PUBLIC_CHANNEL,
            chartUrl([8,8,3,2,1,5,3,2,2,3,1,4,6,3,4,7,5,6,5,5,4,5,5,6,4], ["4AM", "4PM", "4AM"], 0));
    }
 
    touch_start(integer total_number)
    {
        llSay(PUBLIC_CHANNEL,
            chartUrl([8,8,3,2,1,5,3,2,2,3,1,4,6,3,4,7,5,6,5,5,4,5,5,6,4], ["4AM", "4PM", "4AM"], 0));
    }
}