Please post errors in the published version of Algorithms of the Intelligent Web, Second Edition. We'll publish a comprehensive list for everyone's convenience.

Thank you!
Susan Harkins
Errata Editor

Hi,
in Listing 2.1. Interrogating the Iris dataset in scikit-learn (interactive shell)

When trying to reproduce (with full up-to-date ipython) the code, the

np.array(zip(iris.data,iris.target))[0:10]

line fails with this message:

IndexError: too many indices for array

The problem is that np.array creates a 1 dimension array with the zipped object instead of iterating through it to create the desired array.

In order to get the desired behaviour, I had to create a list from the zip object first

np.array(list(zip(iris.data,iris.target)))[0:10]

This is my first dip into numpy, so it might be something due to an update in the library since the book was released

301284 wrote:Hi,
in Listing 2.1. Interrogating the Iris dataset in scikit-learn (interactive shell)

When trying to reproduce (with full up-to-date ipython) the code, the

np.array(zip(iris.data,iris.target))[0:10]

line fails with this message:

IndexError: too many indices for array

The problem is that in python 3 the zip function returns an iterator, not a list as in python2

np.array creates a 1 dimension array with the zipped object instead of iterating through it to create the desired array.

In order to get the desired behaviour, I had to create a list from the zip object first

np.array(list(zip(iris.data,iris.target)))[0:10]

ok sorry for the double post above, I thought the bottom right icon was for editing. Guess it was for quoting. I also found the line that said the provided code was tested on python 2.7.

Listing 2.5. Visualizing the output of k-means has an indentation problem (at least in the epub version)

On both viewers I tried the following code is indented too much on the left:

        axflat.scatter(iris.data[predictions==target,feature_index_x],
               iris.data[predictions==target,feature_index_y],
               c=color,label=label)

        axflat.set_xlabel(feature_names[feature_index_x])
        axflat.set_ylabel(feature_names[feature_index_y])

which mean this part of the code will not be part of the loop and the resulting graph will only draw the last sub graph.

Many thanks for your interest in the book!

301284, can you please confirm that the issue is appropriately captured in the errata.

The current errata list is available at http://www.cantab.net/users/douglas.mcilwraith/errata.htm. Thanks!

Susan Harkins
Errata Editor