Hello, I would like to see an addition to the round(x,n) function syntax that would allow one to specify that x should be rounded to the nth significant digit as opposed to the nth digit to the left or right of the 1's digit. I am testing the waters right now on python-list and have not yet submitted a PEP. Some there have suggested that it be called a different function. Someone else has suggested that perhaps it could be added into SciPy or Numeric as a function there. I prefer the name round because it describes what you are doing. Someone suggested that MATLAB has a function called chop that does what I am proposing and at http://www.math.colostate.edu/~tavener/M561/lab5/lab5.pdf the document says that the "MATLAB function chop(x,n) rounds (not chops!) the number x to n significant digits." If this new function was called "chop" then any previous MATLAB users would know what to expect. (But why call it chop if you are actually rounding?) What I think would be nice is to modify round so it can round to a given number of sig. figs. Here is a def called Round that simulates what I am proposing: from math import floor,log10 def Round(x,n=0): if n%1: d=int(10*n) return round(x,d-1-int(floor(log10(abs(x))))) else: return round(x,n) print Round(1.23456,2) #returns 1.23 print Round(1.23456,0.2) #returns 1.2 The way that I have enhanced round's syntax is to have it check to see if there is a non-zero decimal part to n. If there is, n is multiplied by 10 and the resulting value is used to compute which digit to round x to. n=0.1 will round to the first significant digit while n=0.4 and n=1.1 will round to the 4th and 11th, respectively. I don't believe you will run into any numerical issues since even though something like .3 may be represented internally as 0.29999999999999999, multiplying it by 10 gets you back to 3 and this value is what is used in the call to round() I am open to comments about implementation and function name. /c