ble.appendChild(header)

            let renderData = this.computeRenderData(df)
            for (let j = 0; j < renderData.length; j++) {
                let rowData = renderData[j]
                let tr = document.createElement("tr");
                let isLastRow = j === renderData.length - 1
                header.appendChild(tr);
                for (let i = 0; i < rowData.length; i++) {
                    let cell = rowData[i]
                    let th = document.createElement("th");
              