IPython Notebook Essentials is a solid introduction to IPython Notebook that I would recommend for scientists or others who need to learn to code for their job. IPython Notebook itself is a sort of hybrid of Excel, MATLAB, and Python IDE, and this book touches on a wide range of related topics.
Don't mistake this book for simply covering just IPython on Notebook. The first two chapters teach you the ropes of the software, and the later chapters cover generating graphs with matplotlib, processing & analyzing data with Pandas (a Python software library), and doing more advanced mathematics with the SciPy, Numba, and NumbaPro libraries.
IPython Notebook Essentials is a light introduction (IPython itself is fairly easy to pick up), but the strength of the book is that it brings the reader into contact with several related libraries. The examples in the book might not be exactly relevant to your field, but the skills they demonstrate will be. Following along with them on your own computer will let you get the most from this book. The main criticism I would have of the book is that it is wide but not deep. But if you understand this going into the book, you won't be disappointed.
If you want to learn programming in general, this is not the book for you. If you don't mind haphazardly sorting through free tutorials on the web, then you can learn the same concepts that are presented in this book. But if you are in the particular niche of scientist or administrator who needs to do number crunching, has a small amount of previous Python programming experience, and want a light introduction to the Python ecosystem of data analysis tools, IPython Notebook Essentials is a good start.
Disclosure: I received a free ebook review copy of IPython Notebook Essentials from Packt Publishing for the purposes of writing this review. I do not have any business ties to Packt Publishing.