Reduce function in dc.js

I am new to the dc.js library and wanted to do the crossfilter calculation below on group method of my geochoropleth chart. I am pretty sure there is some function I could pass to the reduce method of group .

I have the following data in DATA.csv (the first row contains column names):

BUDGET,GID,MDIS,USPRO,TYPE,FILEURL,RVID,VERDATE,VERSTAT,SCORE
10428,ALI-G-006,Aliabad,Kunduz,Hard,/uploadedfiles/reports/SIKA North/136-SIKA-North-ALI-G-006.pdf,0,19-08-2014,2,0
24853,ALI-G-008,Aliabad,Kunduz,Hard,/uploadedfiles/reports/SIKA North/561-SIKA-North-ALI-G-008.pdf,0,19-08-2014,0
24831,ALI-G-019,Aliabad,Kunduz,Hard,/uploadedfiles/reports/SIKA North/987-SIKA-North-ALI-G-019.pdf,0,18-08-2014,2,0
24771,IMA-G-017,Imam Sahib,Kunduz,Hard,/uploadedfiles/reports/SIKA North/557-SIKA-North- IMA-G-017.pdf,0,28-08-2014,2,1
21818,IMA-G-019,Imam Sahib,Kunduz,Hard,/uploadedfiles/reports/SIKA North/992-SIKA-North-IMA-G-019.pdf,0,27-08-2014,2,0
12266,KHA-G-007,Khanabad,Kunduz,Hard,/uploadedfiles/reports/SIKA North/583-SIKA-North - KHA-G-007.pdf,0,7/9/2014,1,0
23148,KUN-G-002,Kunduz,Kunduz,Hard,/uploadedfiles/reports/SIKA North/909-SIKA-North - KUN-G-002.pdf,0,1/9/2014,2,0
54584,KUN-G-004,Kunduz,Kunduz,Hard,/uploadedfiles/reports/SIKA North/702-SIKA-North - KUN-G-004 20140709.pdf,0,9/7/2014,1,0
24544,PUL-G-001,Pul-e Khumri,Baghlan,Hard,/uploadedfiles/reports/SIKA North/599-SIKA-North - PUL-G-001 - 20140623.pdf,0,6/7/2014,2,1
40149,SSKDAG046,Arghandab (1),Kandahar,Hard,/uploadedfiles/reports/SIKA South/239-SIKA-South-SSKDAG046.pdf,0,12/9/2014,0,0.625
39452,0003 LGR MAG,Muhammad Aghah,Logar,Hard,/uploadedfiles/reports/SIKA East/792-SIKA-East - 0003 LGR MAG - 20140610.pdf,0,10/6/2014,2,0.7
58298,0013 LGR MAG,Muhammad Aghah,Logar,Hard,/uploadedfiles/reports/SIKA East/591-SIKA-East - 0013 LGR MAG 20140601.pdf,0,1/6/2014,2,0]        

Below is the dimension and group for my chart:

var facts = crossfilter(data);
var scoref = facts.dimension(function (d) { return d.district;});

var scoreg = scoref.group().reduceSum(function(d){return d.score;});

The d.score field's value is calculated using the code below with PHP:

$tempsql = $dbase->query('select "VERMDIS", COUNT(*) AS TOTAL, SUM("VERSTAT") AS SAM FROM mt_fver GROUP BY "VERMDIS"');

while ($r = pg_fetch_array($tempsql)) {
    $dist = $r['VERMDIS'];
    $score = $r[2] / (2 * $r[1]);   
    $disxx[$dist] = $score;
}

What I would like to achieve is to do the same calculation using group().reduce(function (p,v) { /* ... */ }) from the dc.js library while grouping the values by district names.

---

What results/errors are you getting? Looks like pretty much the right idea, but take into account:

if you're using d3.csv() , it will return the values as strings, so you'll need either to preprocess your data, or use +d.score to convert the values while reading them

the field may come out as d.SCORE depending how you are reading the CSV in.

you may need to adapt the reduce function to suit your calculation

If you put a line break in the function you pass to reduce, you can set a breakpoint there using the browser's debugger and experiment on the console to figure out what expression works for what you need.

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