Is it possible to create a new csv column with calculation while importing in Powershell?

Question

I'd like to be able to do something like This except -AddColumn is fictitious syntaxe :

Import-Csv in.csv -header Date,Time,O,H,L,C,V|select * -AddColumn median %{$_.median=($_.H + $_.L)/2}

What would be the real syntax or how to do it the easiest way ?

data file :

2015.08.09,20:45,1.09538,1.09546,1.09522,1.09524,74
2015.08.09,20:50,1.09523,1.09537,1.09505,1.09523,110
2015.08.09,20:55,1.09524,1.09546,1.09520,1.09526,165
2015.08.09,21:00,1.09526,1.09526,1.09495,1.09497,141

possible duplicate of [Add Column to CSV Windows PowerShell](http://stackoverflow.com/questions/17022017/add-column-to-csv-windows-powershell) — Ryan Bemrose, Sep 18 '15 at 19:31

Matt · Accepted Answer · 2015-09-19T00:03:46.323

3

Foreach-Object and Add-Member come to mind but a simpler solution would be to use a calculated property.

Import-Csv in.csv -header Date,Time,O,H,L,C,V | select *, @{Name="median";Expression={([double]$_.H + [double]$_.L)/2}}

Don't forget to cast your numbers for mathematical calculations. Before it was trying to do something like this:

($_.H + $_.L)/2
("1.09538" + "1.09524")/2
(1.095381.09524)/2 # < that would not compute

edited Sep 19 '15 at 00:03

answered Sep 18 '15 at 19:30

Matt

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I have updated with data file. That's weird median is empty, why ? – user310291 Sep 18 '15 at 19:50
@user310291 That is my fault for not paying attention to you calculation. Import-csv casts everything to strings. updated – Matt Sep 18 '15 at 22:55

Is it possible to create a new csv column with calculation while importing in Powershell?

1 Answers1