Add Sum A Bunch Of Numbers In The Current File as a Vim TIL

vim/sum-a-bunch-of-numbers-in-the-current-file.md

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+# Sum A Bunch Of Numbers In The Current File
+
+Let's say I have a bunch of big numbers on consecutive lines in the file I
+currently have open in Vim. Like this:
+
+```
+   418564
+   921550
+  1180181
+  1234458
+  2706100
+ 15954945
+ 16254608
+```
+
+If I make a visual selection of those numbers and then hit `:`, it will open a
+command prompt for the beginning (`'<`) to the end (`'>`) of the visual
+selection. I can then shell out those lines to an external command by starting
+the command with `!`. The command to shell out to for this scenario is `awk`
+which can sum up values from a "file" in a single line.
+
+The whole thing will look like this:
+
+```
+:'<,'>!awk '{s+=$1} END {print s}'
+```
+
+Hit enter. Then `awk` will produce the sum and replace the highlighted lines
+with that value.
+
+```
+38670406
+```
+
+[source](https://stackoverflow.com/a/450821)