Total UNIX Rookie, but I'm learning. I have columns of integer data separated by spaces, and I'm using a Mac terminal.

What I want to do:
1. Compare "line 1 column 2" (x) to "line 2 column 2" (y); is y-x>=100?
2. If yes, display difference and y's line number
3. If no, increment x and y by one and repeat

How I am going about it:

sed -n '1,2 p' datafile | cut -d' ' -f1 #gives me the two fields of interest

Is this a homework?

This is for research. The data is power and its odd harmonics, and I am looking for a way to ID transients without having to graph everything. I just chose simple numbers so I can understand the mechanics. Thanks.

OK,
please post a sample input file and an example of the expected output. Please use code tags: Video tutorial on how to use code tags in The UNIX and Linux Forums.

With assumptions about your data and its structure:

awk '!(NR%2) && (d=$2-x)>=100{print d,NR}{x=$2}' file

data sample, I modified the second column for simplicity:

1.94183e+05  7.8e+04  1.09609e+04  -2.51962e+03  2.58938e+03  -1.78130e+04  8.17326e+03  9.09750e+03  
1.95223e+05  7.8e+04  1.08129e+04  -2.50996e+03  2.23601e+03  -1.76457e+04 8.53983e+03  8.87947e+03  
1.95826e+05  7.8e+04  1.08992e+04  -2.80696e+03  2.35323e+03  -1.77662e+04  8.43230e+03  8.83312e+03  
1.94827e+05  7.62589e+04  1.11074e+04  -2.79142e+03  2.60123e+03  -1.80548e+04  8.05580e+03  8.95096e+03  
1.92552e+05  7.8e+04  1.10656e+04  -2.03271e+03  3.18014e+03  -1.78507e+04  7.77928e+03  9.32247e+03  
1.91165e+05  7.9e+04  1.07475e+04  -1.78148e+03  3.61320e+03  -1.76183e+04  7.69183e+03  9.39564e+03  
1.91355e+05  7.9e+04  1.07990e+04  -2.17165e+03  3.17912e+03  -1.79394e+04  7.87802e+03  9.13235e+03  
1.90294e+05  7.8e+04  1.08781e+04  -2.42501e+03  2.58355e+03  -1.82862e+04  8.15985e+03  8.91582e+03  
1.88968e+05  7.8e+04  1.03374e+04  -2.25564e+03  2.31198e+03  -1.81390e+04  8.48529e+03  8.75009e+03  
1.89367e+05  7.8e+04  1.01039e+04  -1.94181e+03  2.55877e+03  -1.76577e+04  8.55628e+03  8.80059e+03

Your step 3 makes no sense to me. If y-x is not >= 100, then (y+1)-(x+1) can't be >= 100 either. This will just create an very large loop until one of the values overflows. So, until you can explain why this should be done, I'm going to ignore this requirement.

The proposal elixir_sinari makes the assumption that you are only comparing x values on odd numbered lines against y values on even numbered lines. Seeing your sample data and comments in message #6 in this thread, it looks like you want to compare the value in the 2nd column of your input file for every line except the 1st.

This slight modification to elixir_sinari's proposal:

awk '(NR>1) && (d=$2-x)>=100{print d,NR}{x=$2}' file

1741.1 5
1000 6
1741.1 14
1000 15
1741.1 23
1000 24