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You're reading from  Python Data Visualization Cookbook

Product typeBook
Published inNov 2013
Reading LevelIntermediate
PublisherPackt
ISBN-139781782163367
Edition1st Edition
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Author (1)
Igor Milovanovic
Igor Milovanovic
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Igor Milovanovic

Igor Milovanović is an experienced developer, with strong background in Linux system knowledge and software engineering education. He is skilled in building scalable data-driven distributed software rich systems. An evangelist for high-quality systems design, he has a strong interest in software architecture and development methodologies. Igor is always committed to advocating methodologies that promote high-quality software, such as test-driven development, one-step builds, and continuous integration. He also possesses solid knowledge of product development. With field experience and official training, he is capable of transferring knowledge and communication flow from business to developers and vice versa. Igor is most grateful to his girlfriend for letting him spend hours on work instead with her and being an avid listener to his endless book monologues. He thanks his brother for being the strongest supporter. He is also thankful to his parents for letting him develop in various ways to become a person he is today.
Read more about Igor Milovanovic

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Reading files in chunks


Python is very good at handling reading and writing files or file-like objects. For example, if you try to load big files, say a few hundred MB, assuming you have a modern machine with at least 2 GB of RAM, Python will be able to handle it without any issue. It will not try to load everything at once, but play smart and load it as needed.

So even with decent file sizes, doing something as simple as the following code will work straight out of the box:

with open('/tmp/my_big_file', 'r') as bigfile:
    for line in bigfile:
        # line based operation, like 'print line'

But if we want to jump to a particular place in the file or do other nonsequential reading, we will need to use the handcrafted approach and use IO functions such as seek(), tell(), read(), and next() that allow enough flexibility for most users. Most of these functions are just bindings to C implementations (and are OS-specific), so they are fast, but their behavior can vary based on the OS we are running...

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Python Data Visualization Cookbook
Published in: Nov 2013Publisher: PacktISBN-13: 9781782163367

Author (1)

author image
Igor Milovanovic

Igor Milovanović is an experienced developer, with strong background in Linux system knowledge and software engineering education. He is skilled in building scalable data-driven distributed software rich systems. An evangelist for high-quality systems design, he has a strong interest in software architecture and development methodologies. Igor is always committed to advocating methodologies that promote high-quality software, such as test-driven development, one-step builds, and continuous integration. He also possesses solid knowledge of product development. With field experience and official training, he is capable of transferring knowledge and communication flow from business to developers and vice versa. Igor is most grateful to his girlfriend for letting him spend hours on work instead with her and being an avid listener to his endless book monologues. He thanks his brother for being the strongest supporter. He is also thankful to his parents for letting him develop in various ways to become a person he is today.
Read more about Igor Milovanovic