How do I add the nth element for every line in a text file?

Question

Suppose I have a text file, in this format:

1 1 1 1 1 99.5016 10.43 99.5016 99.5016 7.074 47.8012 10.43 7.074 7.074
2 1 1 1 1 99.5016 10.43 99.5016 99.5016 7.074 47.8012 10.43 7.074 7.074
3 1 1 1 1 99.5016 10.43 99.5016 99.5016 7.074 47.8012 10.43 7.074 7.074

And I want to add up all the elements in the ones column, for a certain number of lines. How would I do that?

I have this currently:

data = Import[
  "/Users/myname/Documents/foldername/filename.txt", "Table"]
Total@data[[All, 2]];

Answer 1

You need Import, Part (i.e. [[...]]), probably Span (i.e. ;;), and Total.

Import the data:

data = Import["path\to\yourdatafile.txt", "Table"];

Sum all entries in the first column:

Total@data[[All, 1]]

Sum entries in the third column and in the second to third row:

Total@data[[2 ;; 3, 3]]

Sum entries in column 2, rows 1 and 3:

Total@data[[{1, 3}, 2]]

Answer 2

I figured it out.

data = Import[
  "/Users/myname/Documents/foldername/filename.txt", "Table"]
Total[data, {1}]

Part of the error was that I had an empty row at the end of my text file.