Stata month comparison

drop *
input str9 period_start_string str9 period_end_string
"01Nov2000" "01Jan2000"
"01Dec2000" "01Feb2000"
"01Jan2000" "01Mar2000"
"01Feb2000" "01Apr2000"
end

*Select only the month from the input
gen psd_month_only_str = substr(period_start_string, 3, 3)
gen ped_month_only_str = substr(period_end_string, 3, 3)

*Create date format variable from month only variable above
gen psd_month_only_date = date(psd_month_only_str, "M")
gen ped_month_only_date = date(ped_month_only_str, "M")

*Create month format variable from above date variable taken from month only input
gen psd_month_only_month = month(psd_month_only_date)
gen ped_month_only_month = month(ped_month_only_date)

*check if month only data start > end in MONTH format
if psd_month_only_month > ped_month_only_month{
gen smonth_gt_e_date = 1
}
else{
gen smonth_gt_e_date = 0
}


*begin working with whole date
*take string variable for whole date, create date format variable
gen psd_date = date(period_start_string, "DMY")
gen ped_date = date(period_end_string, "DMY")
format psd_date %d
format ped_date %d

*take date format variable for whole date, create month format variable
gen psd_month = month(psd_date)
gen ped_month = month(ped_date)
*format psd_month %d
*format ped_month %d


gen psd_mofd = mofd(psd_date)
gen ped_mofd = mofd(ped_date)
*format psd_mofd %d
*format ped_mofd %d


*check if start > end in STRING format
if period_start_string > period_end_string{
gen s_gt_e_string = 1
}
else{
gen s_gt_e_string = 0
}

*check if start > end in DATE format
if psd_date > ped_date{
gen s_gt_e_date = 1
}
else{
gen s_gt_e_date = 0
}

*check if start > end in MONTH format
if psd_month > ped_month{
gen s_gt_e_month = 1
}
else{
gen s_gt_e_month = 0
}

*check if start > end in MOFD format
if psd_mofd > ped_mofd{
gen s_gt_e_mofd = 1
}
else{
gen s_gt_e_mofd = 0
}


describe
list

*test one value at a time only
if "01nov1960" > "01jan1960"{
display "True"
}
else{
display "False"
}


if "01jan1960" > "01nov1960"{
display "True"
}
else{
display "False"
}