Could you provide a sample "C:\work\posit.txt" ? You probably need to split your text into lines and pay attention to [ ] vs [[ ]]

Grabbar,

You have a variety of issues in you question (missing brackets, incorrect calls to Take, referencing indices beyond the last value). Focus first on importing the data:

multilineString = Import["posit.txt", "Text"]

"64817367.784333

1234.566

2345.567

3456.890

123

234

456
"

Then split into lines:

listOfStrings = StringSplit[multilineString]

{"64817367.784333", "1234.566", "2345.567", "3456.890", "123", "234", "456"}

And convert the strings to numbers:

listOfNumbers = Map[ToExpression, listOfStrings]

{6.48174*10^7, 1234.57, 2345.57, 3456.89, 123, 234, 456}

After that you can use the Partition command to split the data in sets of 4 and then apply your formula.

Gabbar,

You need to escape the backslashes and add the missing semicolons at the end of each command, or put your commands in multiple cells. In your code you are trying to extract elements from an undefined variable v.

After completing a tutorial like http://www.wolfram.com/language/fast-introduction-for-programmers/en/ everything will make sense.

Regards,

Gustavo