@staticmethod
def _specify_input(recs, idx, ivar, emulate_taxsim_2441_logic):
    """
        Specifies recs values for index idx using ivar input variables.

        Parameters
        ----------
        recs: Records
            Records object containing a row for each tax filing unit.

        idx: integer
            recs index of the tax filing unit whose input is in ivar.

        ivar: dictionary
            input variables for a single tax filing unit.

        emulate_taxsim_2441_logic: boolean

        Returns
        -------
        nothing: void
        """
    recs.RECID[idx] = ivar[1]
    recs.FLPDYR[idx] = ivar[2]
    if ivar[4] == 3:
        mars_value = 4
        num_taxpayers = 1
    else:
        mars_value = ivar[4]
        num_taxpayers = ivar[4]
    recs.MARS[idx] = mars_value
    num_dependents = ivar[5]
    num_eitc_qualified_kids = num_dependents
    recs.EIC[idx] = min(num_eitc_qualified_kids, 3)
    total_num_exemptions = num_taxpayers + num_dependents
    recs.XTOT[idx] = total_num_exemptions
    if ivar[6] < 3:
        recs.age_head[idx] = 50
        recs.age_spouse[idx] = 50
        if ivar[6] >= 1:
            recs.age_head[idx] = 70
            if ivar[6] >= 2:
                recs.age_spouse[idx] = 70
    else:
        recs.age_head[idx] = ivar[6] // 100
        recs.age_spouse[idx] = ivar[6] % 100
    recs.e00200p[idx] = ivar[7]
    recs.e00200s[idx] = ivar[8]
    recs.e00200[idx] = ivar[7] + ivar[8]
    recs.e00650[idx] = ivar[9]
    recs.e00600[idx] = ivar[9]
    recs.e00300[idx] = ivar[10]
    recs.e01700[idx] = ivar[11]
    recs.e02400[idx] = ivar[12]
    recs.e00400[idx] = ivar[13]
    recs.e18500[idx] = ivar[15]
    recs.e18400[idx] = ivar[16]
    recs.e32800[idx] = ivar[17]
    if emulate_taxsim_2441_logic:
        recs.f2441[idx] = num_dependents
    else:
        recs.f2441[idx] = ivar[19]
    recs.e02300[idx] = ivar[18]
    recs.n24[idx] = ivar[19]
    recs.e19200[idx] = ivar[20]
    recs.p22250[idx] = ivar[21]
    recs.p23250[idx] = ivar[22]
