Re: Dealing with irregular shaped arrays

*To*: mathgroup at smc.vnet.net*Subject*: [mg22063] Re: Dealing with irregular shaped arrays*From*: "Mariusz Jankowski" <mjkcc at usm.maine.edu>*Date*: Fri, 11 Feb 2000 02:38:49 -0500 (EST)*Organization*: University of Southern Maine*References*: <87trbn$5ns@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Steve, First a comment: upgrade to version 4 since its functionality for reading data and manipulating arrays is much improved. However, in version 3, the following will work. In[2]:= strm = OpenRead["d:\\temp\\test.txt"] Out[2]= InputStream["d:\\mjkcc\\temp\\test.txt", 5] In[4]:= data = ReadList[strm, Number, RecordLists -> True] Out[4]= {{1, 3, 5}, {2, 2, 1, 3, 7}, {3, 9}, {4, 7, 9, 2}, {5, 2, 1}} Define a padding function. Version 4 has a built-in function. In[5]:= pad[x_, L_] := Join[x, Table["na", {L - Length[x]}]] Find the length of the longest record In[6]:= Max[Length /@ data] Out[6]= 5 Pad each record and transpose In[9]:= arr=Transpose[(pad[#1, %] & ) /@ data] Out[9]= {{1, 2, 3, 4, 5}, {3, 2, 9, 7, 2}, {5, 1, "na", 9, 1}, {"na", 3, "na", 2, "na"}, {"na", 7, "na", "na", "na"}} At this point you are done. A1=arr[[1]]; A2=arr[[2]]; etc Good luck, Mariusz ====================================== Mariusz Jankowski University of Southern Maine email: mjkcc at usm.maine.edu Steve <nospam at nospam.com> wrote in message news:87trbn$5ns at smc.vnet.net... > I need to import and process an irregular shaped array contained in a > tab-delimited text file using version 3.0. The simplified structure > looks like the following 5 rows of data except that in general, the > actual data will not necessarily be integer: > > 1 3 5 > 2 2 1 3 7 > 3 9 > 4 7 9 2 > 5 2 1 > > I need to "pad" the empty slots with a text string such as "N/A" so that > the resulting array will be a complete 5x5 array. Then I need to assign > a unique variable name to each column so that the end result will look > like: > > A={1,2,3,4,5} > B={3,2,9,7,2} > C={5,1,N/A,9,1} > D={N/A,3,N/A,2,N/A} > E={N/A,7,N/A,N/A,N/A} > > I've tried > > in1=OpenRead["Input.txt"] > data=ReadList[in1,Number,RecordLists->True]//TableForm > > which returns the array with the "empty slots" but I don't see how to > partition this into the structure I need. > > Thanks for any help. > > Steve > >