Add Date in Column data

UNIX for Beginners Q & A
1

Hi

Need to add Date to column data as belwo

Input

Date: 2020-04-24
Time Counter C00005A_1 C000B_1
19:00 AC_Sli 10 N/A
19:00 Ac_MG N/A 50
19:00 L_Thhut_MCG 100 N/A

Date: 2020-04-25
Time Counter C00005A_1 C000B_1
19:00 AC_Sli 10 N/A
19:00 Ac_MG N/A 50
19:00 L_Thhut_MCG 100 N/A
20:00 L_Thhut_MCG 100 N/A

Date: 2020-04-26
Time Counter C00005A_1 C000B_1
19:00 AC_Sli 10 N/A
19:00 Ac_MG N/A 54
19:00 L_Thhut_MCG 110 N/A

Output:-

Time Counter C00005A_1 C000B_1
2020-04-24_19:00 AC_Sli 10 N/A
2020-04-24_19:00 Ac_MG N/A 50
2020-04-24_19:00 L_Thhut_MCG 100 N/A
2020-04-25_19:00 AC_Sli 10 N/A
2020-04-25_19:00 Ac_MG N/A 50
2020-04-25_19:00 L_Thhut_MCG 100 N/A
2020-04-25_20:00 L_Thhut_MCG 100 N/A
2020-04-26_19:00 AC_Sli 10 N/A
2020-04-26_19:00 Ac_MG N/A 54
2020-04-26_19:00 L_Thhut_MCG 110 N/A
2

Ok, where exactly are stuck?

3

HI

I have tried something below ..

sed 's/.*\:\(... ... .. ..:..:.. ....\) .*/\1/' $inputfiel
4

I'm afraid that sed script doesn't lead you anywhere. Try

$ awk '/^Date/ {TMP = $2; next} /^Time/ {if (!HDDone++) print; next} !/^ *$/ {print TMP "_" $0}' file
Time Counter C00005A_1 C000B_1
2020-04-24_19:00 AC_Sli 10 N/A
2020-04-24_19:00 Ac_MG N/A 50
2020-04-24_19:00 L_Thhut_MCG 100 N/A
2020-04-25_19:00 AC_Sli 10 N/A
2020-04-25_19:00 Ac_MG N/A 50
2020-04-25_19:00 L_Thhut_MCG 100 N/A
2020-04-25_20:00 L_Thhut_MCG 100 N/A
2020-04-26_19:00 AC_Sli 10 N/A
2020-04-26_19:00 Ac_MG N/A 54
2020-04-26_19:00 L_Thhut_MCG 110 N/A