Wearing dressy clothes in the "lab" I'm a Ph.D. candidate in a theoretical field, so there is only math and programming involved (as opposed to a wet lab). The environment is very casual, everyone just wears jeans and a t-shirt everyday. Sometimes I dress semi-formally (e.g. a dress shirt tucked into nice slacks) just because I like to. I notice people tend to give me quite odd stares when I do this. In the blue hair thread, a highly voted comment remarked:


  I only remember one situation in my field where somebody’s looks were commented on and that was somebody wearing a tie and a suit as a PhD student.


and further in the conference appearance thread (which is a dressier occasion than daily lab work):


  if you are young (&lt;30) , wearing a suit and a tie would probably seem a little weird. 


I'm likely over-thinking this, but is it inappropriate for me to wear dressy clothes in the lab? Obviously it's not offensive or anything, but I wouldn't want to make anyone else feel uncomfortable or have them dislike me for what I wear. Any thoughts?
It is perfectly appropriate since most university dress codes for students is to make sure nothing offensive or too revealing is worn (local definitions for both of those are widely variable). It sounds like you are having trouble working out if it is simply that you are unusual or if it is actually a problem. The simple solution is to ask some of the folks in your lab what they think. 

If it turns out you are worrying on their behalf when they don't care, then keep wearing nice clothes.

If it turns out they care then you actually need to address that, whether by asserting your right to wear what you choose to within the official dress code or by making adjustments. Since clothes are social markers it might be what they perceive to be your statement that is the problem and not the clothes themselves. 

It is always possible they are glaring at you for completely unrelated reasons. Again feeling that out is worth your time. 

A personal story, I wear Hawaiian print shirts every day while teaching. One day I wore a plain button down shirt and my students asked what was wrong. It was laundry day. So don't discount the possibility that the only thing going on is that you stand out from the norm and nothing beyond that.