Median using mobile window bash script

Question

i need to create a file txt that contains a list of Median value that change if i have a file like:

1. 1
2. 2
3. 35
4. 40
5. 50

i want an output like

1. 1
2. 1.5
3. 2
4. 18.5
5. 35

i tried picking up one number at the time from my input file then using sort but i didn't go far.. i hope i made myself clear, thank you!

Answer 1

You could use awk to realize this. For example when you have your data in a file named in.txt:

 awk '{c[NR]=$1; asort(c); if (NR%2) {print c[(NR+1)/2]} else {print (c[(NR/2)]+c[(NR/2)+1]) / 2.0}}' < in.txt

results in the output

1
1.5
2
18.5
35