Method sum

src/danfojs-base/core/frame.ts:1339–1360

* Return the sum of values across an axis. * @param options.axis 0 or 1. If 0, count column-wise, if 1, add row-wise. Defaults to 1 * @example * ``` * const df = new DataFrame([[1, 2], [3, 4]], { columns: ['A', 'B']}) * df.sum().print() * ``` * * @example

(options?: { axis?: 0 | 1 })

     * ```
    */
    sum(options?: { axis?: 0 | 1 }): Series {
        const { axis } = { axis: 1, ...options }

        if ([0, 1].indexOf(axis) === -1) {
            throw Error("ParamError: Axis must be 0 or 1");
        }

        const result = this.$getDataByAxisWithMissingValuesRemoved(axis)
        const sumArr = result.map((innerArr) => {
            return innerArr.reduce((a, b) => Number(a) + Number(b), 0)
        })
        if (axis === 0) {
            return new Series(sumArr, {
                index: [...this.columns]
            })
        } else {
            return new Series(sumArr, {
                index: [...this.index]
            })
        }

    }

    /**
     * Return percentage difference of DataFrame with other.