Programming Leftovers

posted by Roy Schestowitz on Oct 02, 2023

• Just because it's old, doesn't make it tech debt.

  I spent a very long time early in my career incorrectly thinking that obsolete abstractions were tech debt.

  Finding time to reduce tech debt is an important part of balancing development time. Making up for intentional previous trade offs in quality for time is tech debt. A mental model or abstraction can become unsuitable for users as the variety of use cases grows.

  Replacing these abstractions should be a part of product process, not tech maintenance. Replacing abstractions without concrete use cases will lead likely to premature optimization and new abstractions which are unlikely to be correct.

• 50 years later, is Two-Phase Locking the best we can do?

  Two phase locking (2PL) was the first of the general-purpose Concurrency Controls to be invented which provided Serializability. In fact, 2PL gives more than Serializability, it gives Opacity, a much stronger isolation level. 2PL was published in 1976, which incidentally is the year I was born, and it is likely that Jim Gray and his buddies had this idea long before it was published, which means 2PL first came to existence nearly 50 years ago.

  After all that time has passed, is this the best we can do?

  Turns out no, we can do better with 2PLSF, but let's start from the begining

• Lessons From Debugging

  By June 1949, people had begun to realize that it was not so easy to get a program right as had at one time appeared. It was on one of my journeys between the EDSAC room and the punching equipment that the realization came over me with full force that a good part of the remainder of my life was going to be spent in finding errors in my own programs. — Maurice Wilkes, creator of the first stored-program computer, EDSAC

• Jussi Pakkanen: Could we make C arrays memory safe?`Probably not, but let's try anyway

  This is a project that I have wanted to implement for a long time. However it has become quite clear that I don't have the time to do it. Thus you get this blog post instead. If someone wants to try to do this on their own, feel free. If you succeed, it would improve computer security by a fair bit.

• Intuition and Spaced Repetition

• Hubert Figuière: Dev Log September 2023

  It's October 2023.

• 2023.40 Less than 4 weeks

  The Third Raku Conference is less than four weeks away (28 October). These are the presentations that have been accepted so far: Talk submission is still open, as is signup for attendance! Andrew Shitov notes that you can also follow any conference updates on Telegram and Mastodon.

• Python

  • Pandas Variance

    The “DataFrame.var()” method is utilized in Python to determine the variance of single, multiple DataFrame objects of Pandas.

  • Python dict() Function

    The “dict()” function is utilized to create and retrieve the key-value pairs dictionary object by taking the keywords arguments, iterable, or mapping objects.

  • Pandas to Date

    In Python, the “pandas.to_date()” method of the “pandas” library is used to convert an object into a datetime format object.

  • Pandas Nlargest()

    The “DataFrame.nlargest()” method retrieves the particular “n” rows in descending order with the highest value at the top.

  • Pandas Merge by Index

    The “pandas.merge()” method, the “pandas.concat()” method, and the “DataFrame.join()” method is used to merge Pandas DataFrame by index.

  • Pandas Summary Statistics

    In Python, the “DataFrame.describe()” method is used to compute the descriptive summary statistics by not including the Nan values from DataFrame or Series.

  • Pandas Not In

    The NOT IN “~” operator is used along with the “DataFrame.isin()” method of Pandas to filter the rows of single or multiple DataFrame columns.

  • Python Fractions

    In Python, the “fractions.Fraction()” class is used to create the fraction object by taking the numerator and denominator values.

  • Python File seekable() Method

    The Python “file.seekable()” method retrieves the Boolean value to determine whether the specified file stream is seekable or not.

  • Python File fileno() Method

    The “fileno()” method determines the integer of the file descriptor of the stream. It returns an error if the operator system does not use a file descriptor.

  • Python ascii() Function

    The built-in “ascii()” function in Python retrieves the string that escapes the non-ASCII characters in the string using “\x”, and “\u” escapes.

  • Python Format Numbers

    The “str.format()” method, “f-strings” method, “%” operator, and “round()” methods are used to format the input numbers in Python.

  • Pandas Rolling Correlation

    The “DataFrame.Rolling.corr()” method of the Pandas module is utilized to determine the rolling correlation of the Pandas Series or DataFrame.

  • Python File writable() Method

    The “file.writable()” method in Python is utilized to determine whether the input file is writable or not according to the boolean value.

  • Python File isatty() Method

    The “file.isatty()” method in Python is used to determine whether the specified file stream is interactive or connected to a terminal device.

  • Pandas Series to CSV

    The “Series.to_csv()” method is utilized to write a Pandas Series object with index and header to a comma-separated values (CSV) file.

  • Python bin() Function

    In Python, the “bin()” function is utilized to convert a decimal, octal, or hexadecimal value into its binary representation.