module.exports = function lrc (s, key, length, source_key) {
if (!source_key) source_key = 'close'
if (s.lookback.length > length) {
let data = []
for (var i=length-1; i>=0; i--) {
data.push([length-1-i, s.lookback[i][source_key]])
}
let result = regression.linear(data)
s.period[key] = result.equation[1] + result.equation[0]*(length-1)
}
}
.map(series => {
const timeseries = get(bucket, `${series.id}.timeseries`);
const buckets = get(bucket, `${series.id}.buckets`);
if (!timeseries && buckets) {
const meta = get(bucket, `${series.id}.meta`);
const timeseries = {
buckets: get(bucket, `${series.id}.buckets`),
};
set(bucket, series.id, { meta, timeseries });
}
const processor = buildProcessorFunction(processors, bucket, panel, series);
const result = first(processor([]));
if (!result) return null;
const data = get(result, 'data', []);
const linearRegression = regression.linear(data);
result.last = getLastValue(data);
result.slope = linearRegression.equation[0];
return result;
});