Method fillNa

src/danfojs-base/shared/types.ts:261–261

(value: ArrayType1D,
        options?:
            {
                columns?: Array<string>,
                inplace?: boolean
            })

    groupby(col: Array<string>): Groupby
    column(column: string): Series
    fillNa(value: ArrayType1D,
        options?:
            {
                columns?: Array<string>,