Re: simple question about removing elements from a table

• To: mathgroup at smc.vnet.net
• Subject: [mg122391] Re: simple question about removing elements from a table
• From: Bill Rowe <readnews at sbcglobal.net>
• Date: Thu, 27 Oct 2011 06:30:56 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com

```On 10/26/11 at 5:37 PM, mheaney at gmail.com (Michael B. Heaney) wrote:

>data={{-0.5, 0.0321787}, {-0.489, 0.0321691}, {-0.478, 0.032211},
>{-0.467, 0.0321723}, {-0.456, 0.0322448}, {-0.444, 0.0321498},
>{-0.433, 0.032132}, {-0.422, 0.0321804}, {-0.411, 0.0322158}, {-0.4,
>0.0320886},  {-0.233,  0.0320596},  {0.567, 0.00286087}, {0.578,
>-0.00143633}, {0.589, -0.00592979}, {0.6, -0.0113609}}

>I want to remove all of the elements that have a positive first number,
>to get:

>datasubset={{-0.5, 0.0321787}, {-0.489, 0.0321691}, {-0.478,
>0.032211}, {-0.467, 0.0321723}, {-0.456, 0.0322448}, {-0.444,
>0.0321498}, {-0.433, 0.032132}, {-0.422, 0.0321804}, {-0.411,
>0.0322158}, {-0.4, 0.0320886},  {-0.233,  0.0320596}}

>How do I do this?

In[16]:= datasubset = DeleteCases[data, {_?Positive, _}]

Out[16]= {{-0.5, 0.0321787}, {-0.489, 0.0321691}, {-0.478,
0.032211},
{-0.467, 0.0321723}, {-0.456, 0.0322448}, {-0.444, 0.0321498},
{-0.433, 0.032132}, {-0.422, 0.0321804}, {-0.411, 0.0322158},
{-0.4, 0.0320886}, {-0.233, 0.0320596}}

```

• Prev by Date: Re: Coin Toss Sim
• Next by Date: Re: Using values from inside a matrix for a new row
• Previous by thread: Re: simple question about removing elements from a table
• Next by thread: Re: simple question about removing elements from a table