Category Archives: NumPy

Webinar – Python for Professionals: The Complete Guide to Enthought’s Technical Training Courses

View the Python for Professionals Webinar

What: Presentation and Q&A with Dr. Michael Connell, VP, Enthought Training Solutions
Who Should Watch: Anyone who wants to develop proficiency in Python for scientific, engineering, analytic, quantitative, or data science applications, including team leaders considering Python training for a group, learning and development coordinators supporting technical teams, or individuals who want to develop their Python skills for professional applications

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Python is an uniquely flexible language – it can be used for everything from software engineering (writing applications) to web app development, system administration to “scientific computing” — which includes scientific analysis, engineering, modeling, data analysis, data science, and the like.

Unlike some “generalist” providers who teach generic Python to the lowest common denominator across all these roles, Enthought specializes in Python training for professionals in scientific and analytic fields. In fact, that’s our DNA, as we are first and foremost scientists, engineers, and data scientists ourselves, who just happen to use Python to drive our daily data wrangling, modeling, machine learning, numerical analysis, simulation, and more.

If you’re a professional using Python, you’ve probably had the thought, “how can I be better, smarter, and faster in using Python to get my work done?” That’s where Enthought comes in – we know that you don’t just want to learn generic Python syntax, but instead you want to learn the key tools that fit the work you do, you want hard-won expert insights and tips without having to discover them yourself through trial and error, and you want to be able to immediately apply what you learn to your work.

Bottom line: you want results and you want the best value for your invested time and money. These are some of the guiding principles in our approach to training.

In this webinar, we’ll give you the information you need to decide whether Enthought’s Python training is the right solution for your or your team’s unique situation, helping answer questions such as:

  • What kinds of Python training does Enthought offer? Who is it designed for? 
  • Who will benefit most from Enthought’s training (current skill levels, roles, job functions)?
  • What are the key things that make Enthought’s training different from other providers and resources?
  • What are the differences between Enthought’s training courses and who is each one best for?
  • What specific skills will I have after taking an Enthought training course?
  • Will I enjoy the curriculum, the way the information is presented, and the instructor?
  • Why do people choose to train with Enthought? Who has Enthought worked with and what is their feedback?

We’ll also provide a guided tour and insights about our our five primary course offerings to help you understand the fit for you or your team:

View Recording  


michael_connell-enthought-vp-training

Presenter: Dr. Michael Connell, VP, Enthought Training Solutions

Ed.D, Education, Harvard University
M.S., Electrical Engineering and Computer Science, MIT


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Plotting in Excel with PyXLL and Matplotlib

Author: Tony Roberts, creator of PyXLL, a Python library that makes it possible to write add-ins for Microsoft Excel in Python. Download a FREE 30 day trial of PyXLL here.


Plotting in Excel with PyXLL and MatplotlibPython has a broad range of tools for data analysis and visualization. While Excel is able to produce various types of plots, sometimes it’s either not quite good enough or it’s just preferable to use matplotlib.

Users already familiar with matplotlib will be aware that when showing a plot as part of a Python script the script stops while a plot is shown and continues once the user has closed it. When doing the same in an IPython console when a plot is shown control returns to the IPython prompt immediately, which is useful for interactive development.

Something that has been asked a couple of times is how to use matplotlib within Excel using PyXLL. As matplotlib is just a Python package like any other it can be imported and used in the same way as from any Python script. The difficulty is that when showing a plot the call to matplotlib blocks and so control isn’t returned to Excel until the user closes the window.

This blog shows how to plot data from Excel using matplotlib and PyXLL so that Excel can continue to be used while a plot window is active, and so that same window can be updated whenever the data in Excel is updated. Continue reading

Webinar: Work Better, Smarter, and Faster in Python with Enthought Training on Demand

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Enthought Training on Demand Webinar

We’ll demonstrate how Enthought Training on Demand can help both new Python users and experienced Python developers be better, smarter, and faster at the scientific and analytic computing tasks that directly impact their daily productivity and drive results.

View a recording of the Work Better, Smarter, and Faster in Python with Enthought Training on Demand webinar here.

What You’ll Learn

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PyQL and QuantLib: A Comprehensive Finance Framework

Authors: Kelsey Jordahl, Brett Murphy

Earlier this month at the first New York Finance Python User’s Group (NY FPUG) meetup, Kelsey Jordahl talked about how PyQL streamlines the development of Python-based finance applications using QuantLib. There were about 30 people attending the talk at the Cornell Club in New York City. We have a recording of the presentation below.

FPUG Meetup Presentation Screenshot

QuantLib is a free, open-source (BSD-licensed) quantitative finance package. It provides tools for financial instruments, yield curves, pricing engines, creating simulations, and date / time management. There is a lot more detail on the QuantLib website along with the latest downloads. Kelsey refers to a really useful blog / open-source book by one of the core QuantLib developers on implementing QuantLib. Quantlib also comes with different language bindings, including Python.

So why use PyQL if there are already Python bindings in QuantLib? Well, PyQL provides a much more Pythonic set of APIs, in short. Kelsey discusses some of the differences between the original QuantLib Python API and the PyQL API and how PyQL streamlines the resulting Python code. You get better integration with other packages like NumPy, better namespace usage and better documentation. PyQL is available up on GitHub in the PyQL repo. Kelsey uses the IPython Notebooks in the examples directory to explore PyQL and QuantLib and compares the use of PyQL versus the standard (SWIG) QuantLib Python APIs.

PyQL remains a work in progress, with goals to make its QuantLib coverage more complete, the API even more Pythonic, and getting a successful build on Windows (works on Mac OS and Linux now). It’s open source, so feel free to step up and contribute!

For the details, check out the video of Kelsey’s presentation (44 minutes).

And here are the slides online if you want to check the links in the presentation.

If you are interested in working on either QuantLib or PyQL, let the maintainers know!

Exploring NumPy/SciPy with the “House Location” Problem

Author: Aaron Waters

I created a Notebook that describes how to examine, illustrate, and solve a geometric mathematical problem called “House Location” using Python mathematical and numeric libraries. The discussion uses symbolic computation, visualization, and numerical computations to solve the problem while exercising the NumPy, SymPy, Matplotlib, IPython and SciPy packages.

I hope that this discussion will be accessible to people with a minimal background in programming and a high-school level background in algebra and analytic geometry. There is a brief mention of complex numbers, but the use of complex numbers is not important here except as “values to be ignored”. I also hope that this discussion illustrates how to combine different mathematically oriented Python libraries and explains how to smooth out some of the rough edges between the library interfaces.

http://nbviewer.ipython.org/urls/raw.github.com/awatters/CanopyDemoArchive/master/misc/house_locations.ipynb

Advanced Cython Recorded Webinar: Typed Memoryviews

Author: Kurt SmithWebinar_screenshot

Typed memoryviews are a new Cython feature for accessing memory buffers, such as NumPy arrays, without any Python overhead. This makes them very useful for manipulating blocks of memory in Cython directly without calling into the Python-C API.  Typed memoryviews have a clean declaration syntax and have a NumPy-like look and feel, supporting slicing, striding and indexing.

I go into more detail and provide some specific examples on how to use typed memoryviews in this webinar: “Advanced Cython: Using the new Typed Memoryviews”.

If you would like to watch the recorded webinar, you can find a link below (the different formats will play directly in different browsers so check to see which one works for you, and you won’t have to download the whole recording ahead of time):

For all you EPD Users: Canopy v1.1

EPD (Enthought Python Distribution) provided a simple install of Python for scientific computing on the major platforms: Windows, Linux and Mac-OS. Those looking for a clean, straightforward Python stack to unpack into a particular directory found EPD to be pretty ideal.

With the introduction of Enthought Canopy, we began addressing users who are more engineer or scientist than programmer and were much less familiar with command-line interfaces. The Canopy desktop (in the vein of MATLAB or Spyder) aims at these technical users who want to use Python, but more as an application or IDE. To implement the desktop in Python and to allow both it and a user-defined Python environment to co-exist and be separately updated, we used virtual environments. As a consequence Canopy can feel a bit foreign to EPD users. With 1.1 we have added a new command line interface (CLI) that will hopefully make EPD users feel more at home in Canopy while retaining many of the Canopy advantages such as in-place update and virtual environment support.

Now, EPD users who just want to use Canopy as a plain Python environment with their own tools or IDE can easily create one or more Python environments. For example, from the command line on Windows:

        Canopy_cli.exe setup C:\Python27

or on Linux:

        canopy_cli setup ~/canopy

The target directory can be any you choose. If you want to make this Python environment the default on your system, you can specify the –default switch, and Canopy will add the appropriate bin directory (Scripts directory on Windows) to your PATH environment variable. On Mac OS and Linux systems, Canopy does this by appending a line to your ~/.bash_profile file which activates the correct virtual environment. On Windows, this Python environment is also added to the system registry so third-party tools can correctly find it.

Since we use virtual environments, the installation layout for Canopy is different. With Canopy we install what is referred to as “Canopy Core”: the core Python environment and a minimum set of packages needed to bootstrap Canopy itself. With it we can lock down the Canopy environment, facilitate the automatic update mechanism, and provide reliable startup and fail-safe recovery. For the user, there is a different environment. This means when a Python update comes out, it is no longer necessary to install a whole new environment plus all of your packages and get everything working again. Instead, simply update Canopy and go back to working — all of your packages are still installed but Python has been upgraded.

To complete an install, Canopy creates two virtual environments named ‘System’ and ‘User’. System is where the Canopy GUI runs; no user code runs in this environment. Updates to this virtual environment are done via the Canopy update mechanisms. The User environment is where the kernel and all user code runs. This virtual environment is managed by Package Manager from the desktop or by enpkg from the command line; any packages can be updated and installed without fear of disrupting the GUI. Similarly, updates to the Canopy GUI will not affect packages installed in the User environment and break your code.

So why stick with virtual environments for an “EPD-like” install? One of the big challenges with the old, “flat” EPD installation method was updating an install, or trying out different package configurations. With virtual environments, you can create a new environment which inherits packages from another virtual environment, and try out a few package changes. When you are satisfied, it’s straightforward to throw away the experimentation area and make the changes to the original, stable virtual environment.

For more details, check out Creating an EPD-like Python environment in our online docs. And you can download Canopy v1.1 now.

Canopy v1.1 – Linux, Command Line Interface and More

Final-version-canopy-logo (1)

With version 1.1, Enthought Canopy now:

1) addresses, much more completely, the command line use cases that EPD users and IT managers expect from their Python distributions,

2) makes Linux support generally available,

3) streamlines installation for users without internet access with full, single-click installers,

4) supports multiple virtual environments for advanced users via “venv” backported to Python 2.7, and

5) provides updates like numpy 1.7.1, matplotlib 1.3.0 and more.

It’s been just over 4 months since Canopy v1.0 shipped with the new desktop analysis environment and our updated Python distribution for scientific computing. Canopy’s analysis environment seems to be well-received by users looking for a simpler GUI environment, but the Canopy graphical installation process left something to be desired by our EPD users.

Along with the Canopy desktop for users that don’t want to work directly from a command line, Canopy version 1.1 now provides command-line utilities that streamline the installation of a complete Python scientific stack for current EPD users who want to work from the shell or command line. In addition, IT groups or tools specialists that need to manage a central install of Python for a workgroup or department now have the tools they need to install and maintain Canopy. Version 1.1’s command-line installation and setup (and the 1-click, full installers detailed below) are much better for supporting Canopy installations on clusters as well.

Canopy for Linux is now fully released. We have full, tested support for RedHat5, CentOS5, and Ubuntu 12.04. Linux distros and versions beyond those work as well (anecdotally and based on some in-house use), but those are our tested versions.

With Canopy v1.0 we implemented a 2-step installation process. The installer includes the Canopy desktop, the Python packages needed by Canopy itself, and other core scientific Python stack packages for a minimal install (the libraries in Canopy Express). For those with a subscription, the second step requires downloading any additional packages using the Package Manager. This 2-step process is problematic for users that don’t have easy internet access or need to install centrally for a group. To help, we now provide full installers with all the Python packages we support included. This provides a streamlined 1-step install process for those who need it or want it.

To ensure users can install any package updates they wish without messing up package dependencies for Canopy itself, we use virtual environments under the hood. With v1.1 we now provide command-line access to our backport of “venv”. The new CLI provides utilities to create, upgrade, activate and deactivate your own virtual environments. Now its much easier to try out new Python environments or set up multiple configurations for a workgroup.

Canopy v1.1 ships many updates to packages and many new ones: OpenCV, LLVM, Bottleneck, gevent, msgpack, py, pytest, six, NLTK, Numba, Mock, patsy and more. You can see the full details on the Canopy Package Index page.

We hope you find version 1.1 useful!