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Re: Removing rows from a table

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  • Subject: [mg128712] Re: Removing rows from a table
  • From: bsyehuda at gmail.com
  • Date: Mon, 19 Nov 2012 04:09:57 -0500 (EST)
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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 at 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.
>
>
>




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