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Topic: Removing rows from a table
Replies: 3   Last Post: Nov 21, 2012 7:50 PM

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 yehuda ben-shimol Posts: 302 Registered: 2/11/05
Re: Removing rows from a table
Posted: Nov 19, 2012 5:05 PM

DeleteCases looks like a perfect solution to your need
here is some data which is replication of what you posted, with some
"modification"

data = {

{{2008, 2, 1, 12, 0, 0.0}, {2008, 2, 15, 12, 0, 0.0}},
{{2009, 2, 1, 12, 0, 0.0}, {2009, 2, 15, 12, 0, 0.0}},
{{2010, 2, 1, 12, 0, 0.0}, {2010, 2, 15, 12, 0, 0.0}},

{{2010, 7, 1, 12, 0, 0.0}, {2010, 7, 15, 12, 0, 0.0}},

{{2011, 7, 1, 12, 0, 0.0}, {2011, 7, 15, 12, 0, 0.0}},
{{2011, 8, 1, 12, 0, 0.0}, {2011, 8, 15, 12, 0, 0.0}}}

Now, to remove the specific row, say the one that starts with {2010,7,1,...

use

DeleteCases[data, {{2010, 7, 1, ___}, _}]

Thats it

yehuda

On Mon, Nov 19, 2012 at 12:14 AM, Citzen90210 <peter_bodon@hotmail.com>wrote:

> Total nubie here and struggling!
>
> I have a dataset of approximately 100,000 records of data points recorded
> at 15 minute intervals. Each row looks something like this:
>
> {"01/01/2010 06:15", 0.04375, 4.96188, 1.00885, 0, 0, 0}
>
> I've worked out how to parse the date column so that seems to be under
> control but now I have a list of date ranges that I need to remove from the
> dataset. The date ranges to be removed look something like this:
>
> {{2010, 2, 1, 12, 0, 0.0}, {2010, 2, 15, 12, 0, 0.0}},
> {{2010, 7, 1, 12, 0, 0.0}, {2010, 7, 15, 12, 0, 0.0}}
>
> with the first column representing the start date of the block to be
> removed and the second column representing the end date of the block,
> multiple rows represent multiple blocks to be removed and the total number
> of blocks is variable.
>
> Ideally I'd like to be able to use Drop or Delete to remove the offending
> blocks of data but I want to be able to somehow feed the command with the
> date range table and have it remove the ranges all in one go.
>
> I'm not having much luck working this out for myself and would love to get
> a few pointers.
>
>
>

Date Subject Author
11/19/12 yehuda ben-shimol
11/21/12 Dana DeLouis
11/21/12 Dana DeLouis