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Math'ca - Can't get a function to read in data

  1. Mar 15, 2009 #1
    SOLVED - Math'ca - Can't get a function to read in data

    I'm trying to do a maximum likelihood estimation in Mathematica. My data was in a text file and I read it into a table. Each entry in the table is two values, like {{1,2},{3,4},...}. I have a 2D function, P[x,y] and when I try and evaluate at a data point, P[data[[1]]], for instance, it doesn't input the values. It just returns P[{1,2}] (with the data in this example).

    Now, it works fine when the data and function are one-dimensional. So this tells me the data is not stored in a manner that the function can immediately use. The problem here is that for me to use the Max Likelihood function, I need the data to be in the proper format. The arguments for the ML function are ML[data,f,param], so it needs to enter the data into the function. So, is there a way I can make a table or list of {x,y} data that could possibly work in this scenario?

    As an aside, there must be because an example of this ML uses multi valued data. I can't get it work with mine though. Argh!

    Thanks thank thanks to anyone who can help!
     
    Last edited: Mar 15, 2009
  2. jcsd
  3. Mar 15, 2009 #2
    Okay, I managed to figure this one out, and get a bit of Mathematica skill in the process.

    If P is my Poisson function, I had to remap it into another function like so:

    i = MapAll[Function[w, Apply[P, w]], #] &;

    where w is a place holder variable, Apply is a math'ca function that turns list elements into function arguments, and MapAll applies every subpart of the list element to the function. Now my function can crawl over all of the data in a table, or accept a single element as input.
     
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