Re: Mapping A Condition Across Two Different Lists
- To: mathgroup at smc.vnet.net
- Subject: [mg91766] Re: Mapping A Condition Across Two Different Lists
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Sun, 7 Sep 2008 05:38:47 -0400 (EDT)
On 9/6/08 at 2:06 AM, gregory.lypny at videotron.ca (Gregory Lypny)
wrote:
>Not sure how to do this using Map, or even if it's possible.
>I can compare a target value to each value in a list like this.
>targetX = 5; listX = {4, 9, 2, 11, 4}; targetX > # & /@ listX
>{True, False, True, False, True}
>I can do the same for another target and another list.
>
>targetY = 3; listY = {4, 0, 1, 8, 6}; targetY > # & /@ listY
>{False, True, True, False, False}
>But can I do it in a similar way for the AND or OR condition without
>having to resort to the Table command?
You could do it with Map as follows:
In[4]:= (targetY > First@# && targetX > Last@#) & /@
Transpose@{listY, listX}
Out[4]= {False,False,True,False,False}
but MapThread is specifically designed for this task. For example,
In[5]:= MapThread[targetY > #1 && targetX > #2 &, {listY, listX}]
Out[5]= {False,False,True,False,False}