I am new to weka and trying to analyse a dataset.
I imported a csv into the explorer window and noticed that one column from the csv file that contains numeric values as percentages (e.g. 46%) has been imported as nominal.
How can I transform these values from nominal to numerical?
Any tips would be much appreciated.
The quickest way would be:
open the CSV file in a text editor
remove all the %
re-import the CSV file in Weka
Other tools, like the Spreadsheet file viewer or the Flow editor in ADAMS, allow you that kind of conversion on the fly using the SpreadSheetConvertCells transformer:
finder: define the correct column range to operate on
conversion: adams.data.conversion.StringExpression -expression "substitute(X, \\\"%\\\", \\\"\\\")"
I have a consistent bpmn file (similar to xml file) and i would like to read it with matlab and store the all file data in one string or char attribute. I have tried with textread(file, format) but the best i can have is a 2358796x1 char and then assemble each line to recreate the file but it's a very long process.
Is there another function to do this ?
Thanks for helping.
You can use this xml2struct.m function, to read xml files and convert all the content to MATLAB struct variable.
Newer versions of Matlab ship with an xmlread function. Have you taken a look at that?
I am new to Xtext.
I want to produce ouptput in generator.xtend based on xml configuration file.
My goal is to have the same grammar, but based on xml configuration file I want to produce different output in generator.
Can I get some advice?
I am reaidng files on HDFS via scalding, aggregating on some fields, and writing to a tab delimited file via TSV. How can I write out a file that contains the schema of my output file? For example,
UnpackedAvroSource(args("input"))
.project('key, 'var1)
.groupBy('key){_.sum[Long]('var1 -> var1sum))}
.write(Tsv(args("output")))
I want to write an output text file that contains "Key, var1sum" that someone who picks up my ooutput file later knows what the columns. I'm assuming scalding doesn't embed this in the file somewhere?
Thanks.
Just found the option writeHeader = true which will write the column names to the output file, negating the need for writing out to a file.
there are datasets in .mat format in the this site: http://www.cs.nyu.edu/~roweis/data.html
I want to change the format to .csv.
Can someone tell me how to change the format to create the .csv file.
Thanks!
Suppose that the .mat files from the site are available already. In the command window in Matlab, you may write, for example:
load('C:\Users\YourUserName\Downloads\mnist_all.mat');
to load the .mat file; the result should be a set of matrices test0, test1, ..., train0, train1 ... created in your workspace, which you want saved as CSV files. Because they're different size, you need to save one CSV per variable, e.g. (also in the command window):
csvwrite('C:\Users\YourUserName\Downloads\mnist_test0.csv', test0);
Repeat the command for each variable, and do not forget to change also the name of the output file to avoid overwriting.
Did you tried the csvwrite function in Matlab?
Just load your .mat files with the load function and then write them with csvwrite!
I do not have a Matlab license so I installed GNU Octave 4.2.1 (2017) on Windows 10 (thank you to John W. Eaton and others). I was not fully successful using the csvwrite so I used the following workaround. (BTW, I am totally incompetent in the Octave world. csvwrite worked for simple data structures).
In the Command Window I used the following two commands
load myfile.mat
save("-text","myfile.txt","variablename")
When the "myfile.mat" is loaded, the variable names for the data vectors loaded are displayed in the workspace window. This is the name(s) to use in the save command. Some .mat files will load several data structures.
The "-text" option is the default, so you may not need to include this option in the command.
The output file lists the .mat file contents in text format as single column (of potentially sequential variables). It should be easy to use you text editor to massage this data into the original matrix structure for use in whatever app you are comfortable with.
Had a similar issue. Needed to convert a series of .mat files that had two columns of numerical data into standard data files (ascii text). Note that I don't really ever use csv, but everything here could be adapted by using csvwrite instead of the standard save.
Using Octave 4.2.1 ....
load myfile.mat
LI = [L, I] ## L and I are column vectors representing my data
save myfile.txt LI
Note that L and I appear to be default variable names chosen by Octave for the two columns vectors in my original data file. Ideally a script that iterated over all files with the .mat extension in my directory would be ideal, but this got the job done. It saves the data as two space separated columns of data.
*** Update
The following script works on Octave 4.2.1 for a series of data files with the .mat extension that are in the same directory. It will iterate over them and write the data out to text files with the same name but with the extension .dat . Note that this is not efficient, so if you have a lot of files or if they are large it can take a while to run. I would suggest that you run it from the command line using octave mat2dat.m so you can actually watch it go.
I make no guarantees that this will work for you, but it did for me. I also am NOT proficient in Octave or Matlab, so I'm sure a better solution exists.
# mat2dat.m
dirlist = glob("*.mat")
for i=1:length(dirlist)
filename = dirlist{i,1}
load(filename, "L", "I")
LI = [L,I]
tmpname = filename(1:length(filename)-3)
txtname = strcat(tmpname, 'dat')
save(txtname, "LI")
end