*Is there an implementation of the Remez algorithm in Julia,or is someone 
working on this?*

Sometimes it is important to have a (polynomial) *minmax approximation* to 
a curve or function (on a finite interval), i.e., an approximating 
polynomial of a certain maximum degree such that the maximum (absolute) 
error is minimized.

A least-squares approach will not work. For example, given a hundred or 
more discrete points representing the Runge function on [-1, 1], package 
*CurveFit* will generate a polynomial of degree 10 that has a maximum 
distance of about 0.10..., while the true minimax solution will have a 
maximal distance of about 0.06... !

The Remez algorithm <http://en.wikipedia.org/wiki/Remez_algorithm> solves 
this problem applying an iterative procedure. As Nick Trefethen has once 
said about other implementations of this algorithm:

    "One can find a few other computer programs in circulation, but 
overall, it 
     seems that there is no widely-used program at present for computing 
best 
     approximations"

The most reliable and accurate existing realization nowadays appears to be 
the one available in Trefethen's MATLAB toolbox *chebfun*, operating with 
Chebyshev approximations -- perhaps package *ApproxFun* would be a good 
starting point.

I thought that Julia might be an appropriate scientific computing 
environment to realize an efficient and accurate version of the Remez 
algorithm. I am considering doing it myself, but would prefer if someone 
with a better command of Julia has already done this.

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