Function prepareSource

libs/echarts/echarts.simple.js:20693–20734

* [Caution]: * MUST be called after series option merged and * before "series.getInitailData()" called. * * [The rule of making default encode]: * Category axis (if exists) alway map to the first dimension. * Each other axis occupies a subsequent dimension. * * [Why make default encode]: *

(seriesModel)

 * @param {module:echarts/model/Series} seriesModel
 */
function prepareSource(seriesModel) {
    var seriesOption = seriesModel.option;

    var data = seriesOption.data;
    var sourceFormat = isTypedArray(data)
        ? SOURCE_FORMAT_TYPED_ARRAY : SOURCE_FORMAT_ORIGINAL;
    var fromDataset = false;

    var seriesLayoutBy = seriesOption.seriesLayoutBy;
    var sourceHeader = seriesOption.sourceHeader;
    var dimensionsDefine = seriesOption.dimensions;

    var datasetModel = getDatasetModel(seriesModel);
    if (datasetModel) {
        var datasetOption = datasetModel.option;

        data = datasetOption.source;
        sourceFormat = inner$3(datasetModel).sourceFormat;
        fromDataset = true;

        // These settings from series has higher priority.
        seriesLayoutBy = seriesLayoutBy || datasetOption.seriesLayoutBy;
        sourceHeader == null && (sourceHeader = datasetOption.sourceHeader);
        dimensionsDefine = dimensionsDefine || datasetOption.dimensions;
    }

    var completeResult = completeBySourceData(
        data, sourceFormat, seriesLayoutBy, sourceHeader, dimensionsDefine
    );

    inner$3(seriesModel).source = new Source({
        data: data,
        fromDataset: fromDataset,
        seriesLayoutBy: seriesLayoutBy,
        sourceFormat: sourceFormat,
        dimensionsDefine: completeResult.dimensionsDefine,
        startIndex: completeResult.startIndex,
        dimensionsDetectCount: completeResult.dimensionsDetectCount,
        // Note: dataset option does not have `encode`.
        encodeDefine: seriesOption.encode
    });
}

// return {startIndex, dimensionsDefine, dimensionsCount}
function completeBySourceData(data, sourceFormat, seriesLayoutBy, sourceHeader, dimensionsDefine) {