Re: real newbie question

*To*: mathgroup at smc.vnet.net*Subject*: [mg64421] Re: real newbie question*From*: Bill Rowe <readnewsciv at earthlink.net>*Date*: Thu, 16 Feb 2006 03:05:33 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

On 2/15/06 at 3:32 AM, Skip.Egley at synopsys.com (Skip Egley) wrote: >Sorry for the newbieness. This is probably a piece of cake for you >folks. >I have a set of Brillouin zone data. That is, there's a kx, ky, and >a kz followed by an energy value. How can I select particular >directions in the Brillouin zone out of this data and make a 2D >plot of it. A k value followed by an energy value. For instance, >say I want to plot along the kx axis. I would need to select all kx >values such that ky and kz were zero and grab the matching energy >value for the kx value. Or if I wanted to plot along a (110) >direction, I would need to grab all kx=ky values with kz=0, along >with the corresponding energy. Get my drift? >Once I have the data I do know how to plot it (not that much of a >newbie) :) So, I take it your problem is how to select the desired values from the original data structure. There are a number of ways this can be done using Select, Cases or Pick. Assuming the data looks like a list of (kx,ky,kz,energy} values, Cases[data, {_,0,0,_}] would give you all instances where ky=kz=0 and Cases[data,_{a_,a_,0,_} would give you all instances where kx=ky and kz = 0 -- To reply via email subtract one hundred and four

**Follow-Ups**:**Re: Re: real newbie question***From:*Pratik Desai <pdesai1@umbc.edu>