Re: Selecting Rows Where All Columns Satisfy a Condition

*To*: mathgroup at smc.vnet.net*Subject*: [mg82609] Re: Selecting Rows Where All Columns Satisfy a Condition*From*: Albert <awnl at arcor.net>*Date*: Fri, 26 Oct 2007 05:18:48 -0400 (EDT)*References*: <ffppu6$l6g$1@smc.vnet.net>

Gregory Lypny wrote: > Hello everyone > > I've got an Nx4 numeric array called X. I'd like to pull out all > rows where -9 does not appear in any of the four columns. I know I > can this: > > Select[X, #[[1]] != -9 && #[[2]] != -9 && #[[3]] != -9 && #[[4]] != > -9 &] > > But is there a more elegant way that applies the not-equal-to > condition to each column without having to repeat it? if there are only integer numbers within your array, you can use: Select[lst,FreeQ[#, -9] &] to be on the save side, you might want to restrict FreeQ to look at the entries at level 1 in the rows only: Select[lst,FreeQ[#,-9,{1}]&] the level restriction makes a difference in cases like: lst={{a-9,5,6,3},{b[-9],0,-5,4}} hth, albert