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Release 0.1.0

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After refurbishing the project we prepare a new relaease.
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Alexander Hess 2024-04-08 22:13:31 +02:00
commit 94e5112f10
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10
03_conditionals/00_content.ipynb
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@ -8,7 +8,7 @@
}
},
"source": [
"**Note**: Click on \"*Kernel*\" > \"*Restart Kernel and Clear All Outputs*\" in [JupyterLab](https://jupyterlab.readthedocs.io/en/stable/) *before* reading this notebook to reset its output. If you cannot run this file on your machine, you may want to open it [in the cloud <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_mb.png\">](https://mybinder.org/v2/gh/webartifex/intro-to-python/develop?urlpath=lab/tree/03_conditionals/00_content.ipynb)."
"**Note**: Click on \"*Kernel*\" > \"*Restart Kernel and Clear All Outputs*\" in [JupyterLab](https://jupyterlab.readthedocs.io/en/stable/) *before* reading this notebook to reset its output. If you cannot run this file on your machine, you may want to open it [in the cloud <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_mb.png\">](https://mybinder.org/v2/gh/webartifex/intro-to-python/main?urlpath=lab/tree/03_conditionals/00_content.ipynb)."
]
},
{
@ -30,7 +30,7 @@
}
},
"source": [
"We analyzed every aspect of the `average_evens()` function in [Chapter 2 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/develop/02_functions/00_content.ipynb) except for the `if`-related parts. While it does what we expect it to, there is a whole lot more to learn by taking it apart. In particular, the `if` may occur within both a **statement** or an **expression**, analogous as to how a noun in a natural language can be the subject of *or* an object in a sentence. What is common to both usages is that it leads to code being executed for *parts* of the input only. It is a way of controlling the **flow of execution** in a program.\n",
"We analyzed every aspect of the `average_evens()` function in [Chapter 2 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/main/02_functions/00_content.ipynb) except for the `if`-related parts. While it does what we expect it to, there is a whole lot more to learn by taking it apart. In particular, the `if` may occur within both a **statement** or an **expression**, analogous as to how a noun in a natural language can be the subject of *or* an object in a sentence. What is common to both usages is that it leads to code being executed for *parts* of the input only. It is a way of controlling the **flow of execution** in a program.\n",
"\n",
"After deconstructing `if` in the first part of this chapter, we take a close look at a similar concept, namely handling **exceptions**."
]
@ -150,7 +150,7 @@
}
},
"source": [
"There are, however, cases where the `==` operator seems to not work intuitively. [Chapter 5 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/develop/05_numbers/00_content.ipynb#Imprecision) provides more insights into this \"bug.\""
"There are, however, cases where the `==` operator seems to not work intuitively. [Chapter 5 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/main/05_numbers/00_content.ipynb#Imprecision) provides more insights into this \"bug.\""
]
},
{
@ -351,7 +351,7 @@
}
},
"source": [
"Let's not confuse the boolean `False` with `None`, another built-in object! We saw the latter before in [Chapter 2 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/develop/02_functions/00_content.ipynb#Function-Definitions) as the *implicit* return value of a function without a `return` statement.\n",
"Let's not confuse the boolean `False` with `None`, another built-in object! We saw the latter before in [Chapter 2 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/main/02_functions/00_content.ipynb#Function-Definitions) as the *implicit* return value of a function without a `return` statement.\n",
"\n",
"We might think of `None` indicating a \"maybe\" or even an \"unknown\" answer; however, for Python, there are no \"maybe\" or \"unknown\" objects, as we see further below!\n",
"\n",
@ -438,7 +438,7 @@
}
},
"source": [
"`True`, `False`, and `None` have the property that they each exist in memory only *once*. Objects designed this way are so-called **singletons**. This **[design pattern <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_wiki.png\">](https://en.wikipedia.org/wiki/Design_Patterns)** was originally developed to keep a program's memory usage at a minimum. It may only be employed in situations where we know that an object does *not* mutate its value (i.e., to reuse the bag analogy from [Chapter 1 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/develop/01_elements/00_content.ipynb#Objects-vs.-Types-vs.-Values), no flipping of $0$s and $1$s in the bag is allowed). In languages \"closer\" to the memory like C, we would have to code this singleton logic ourselves, but Python has this built in for *some* types.\n",
"`True`, `False`, and `None` have the property that they each exist in memory only *once*. Objects designed this way are so-called **singletons**. This **[design pattern <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_wiki.png\">](https://en.wikipedia.org/wiki/Design_Patterns)** was originally developed to keep a program's memory usage at a minimum. It may only be employed in situations where we know that an object does *not* mutate its value (i.e., to reuse the bag analogy from [Chapter 1 <img height=\"12\" style=\"display: inline-block\" src=\"../static/link/to_nb.png\">](https://nbviewer.jupyter.org/github/webartifex/intro-to-python/blob/main/01_elements/00_content.ipynb#Objects-vs.-Types-vs.-Values), no flipping of $0$s and $1$s in the bag is allowed). In languages \"closer\" to the memory like C, we would have to code this singleton logic ourselves, but Python has this built in for *some* types.\n",
"\n",
"We verify this with either the `is` operator or by comparing memory addresses."
]