Update sympy page based on week 1.8 stuff (#11)

* added sympy

* Update references.bib

* Update _toc.yml

* renamed folder

* Update references.bib

* Update sympy.ipynb

* 2 edits

---------

Co-authored-by: Tom van Woudenberg <t.r.vanwoudenberg@tudelft.nl>

Author: rlanzafame

…her_python_stuff/year2/sympy/sympy.ipynb book/08/sympy.ipynbother_python_stuff/year2/sympy/sympy.ipynb renamed to book/08/sympy.ipynb other_python_stuff/year2/sympy/sympy.ipynb renamed to book/08/sympy.ipynb

@@ -409,14 +409,37 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Notice something in the above example. When we typed `expr - x`, we did not get $x + 2y - x$, but rather just $2y$. The $x$ and the $-x$ automatically canceled one another. This is similar to how $\\sqrt{8}$ automatically turned into $2\\sqrt{2}$ above. This isn’t always the case in SymPy;  Aside from obvious simplifications like $x - x = 0$ and $\\sqrt{8} = 2\\sqrt{2}$, most simplifications are not performed automatically. "
+    "Notice something in the above example. When we typed `expr - x`, we did not get $x + 2y - x$, but rather just $2y$. The $x$ and the $-x$ automatically canceled one another. This is similar to how $\\sqrt{8}$ automatically turned into $2\\sqrt{2}$ above. This isn’t always the case in SymPy, however; consider this example:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "image/png": "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",
+      "text/latex": [
+       "$\\displaystyle x \\left(x + 2 y\\right)$"
+      ],
+      "text/plain": [
+       "x⋅(x + 2⋅y)"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
+   "source": [
+    "x*expr"
    ]
   },
   {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "A general formula to simplify formulas is `sym.simplify`, which attempts to apply all of these functions in an intelligent way to arrive at the simplest form of an expression:"
+    "Aside from obvious simplifications like $x - x = 0$ and $\\sqrt{8} = 2\\sqrt{2}$, most simplifications are not performed automatically. A general formula to simplify formulas is `sym.simplify`, which attempts to apply all of these functions in an intelligent way to arrive at the simplest form of an expression:"
    ]
   },
   {
@@ -1139,7 +1162,7 @@
    "source": [
     ":::{card} Test yourself!\n",
     "\n",
-    "Create a symbolic expression representing [Newton's Law of Universal Gravitation](https://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation). Use `sym.lambdify()` to evaluate the expression for two mass of 5.972E24 kg and 80 kg at a distance of 6371 km apart to find the gravitational force in Newtons. $G$ equals $6.67430\\cdot 10 ^{11}$\n",
+    "Create a symbolic expression representing [Newton's Law of Universal Gravitation](https://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation). Use `sym.lambdify()` to evaluate the expression for two mass of 5.972E24 kg and 80 kg at a distance of 6371 km apart to find the gravitational force in Newtons. $G$ equals $6.67430\\cdot 10 ^{-11}$\n",
     "\n",
     "All variables have been defined with:\n",
     "```python\n",

…n_stuff/year2/sympy/sympy_stripped.ipynb book/08/sympy_stripped.ipynbother_python_stuff/year2/sympy/sympy_stripped.ipynb renamed to book/08/sympy_stripped.ipynb other_python_stuff/year2/sympy/sympy_stripped.ipynb renamed to book/08/sympy_stripped.ipynb

@@ -313,7 +313,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Notice something in the above example. When we typed `expr - x`, we did not get $x + 2y - x$, but rather just $2y$. The $x$ and the $-x$ automatically canceled one another. This is similar to how $\\sqrt{8}$ automatically turned into $2\\sqrt{2}$ above. This isn’t always the case in SymPy, however:"
+    "Notice something in the above example. When we typed `expr - x`, we did not get $x + 2y - x$, but rather just $2y$. The $x$ and the $-x$ automatically canceled one another. This is similar to how $\\sqrt{8}$ automatically turned into $2\\sqrt{2}$ above. This isn’t always the case in SymPy, however; consider this example:"
    ]
   },
   {
@@ -344,14 +344,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Notice something in the above example. When we typed `expr - x`, we did not get $x + 2y - x$, but rather just $2y$. The $x$ and the $-x$ automatically canceled one another. This is similar to how $\\sqrt{8}$ automatically turned into $2\\sqrt{2}$ above. This isn’t always the case in SymPy;  Aside from obvious simplifications like $x - x = 0$ and $\\sqrt{8} = 2\\sqrt{2}$, most simplifications are not performed automatically. "
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "A general formula to simplify formulas is `sym.simplify`, which attempts to apply all of these functions in an intelligent way to arrive at the simplest form of an expression:"
+    "Aside from obvious simplifications like $x - x = 0$ and $\\sqrt{8} = 2\\sqrt{2}$, most simplifications are not performed automatically. A general formula to simplify formulas is `sym.simplify`, which attempts to apply all of these functions in an intelligent way to arrive at the simplest form of an expression:"
    ]
   },
   {
@@ -516,7 +509,13 @@
     "\n",
     "Create an expression for the normal distribution function:\n",
     "\n",
-    "$$\\frac{1}{\\sqrt{2\\pi\\sigma}}e^{\\frac{(x-\\mu)^2}{2\\sigma^2}}$$"
+    "$$\\frac{1}{\\sqrt{2\\pi\\sigma}}e^{\\frac{(x-\\mu)^2}{2\\sigma^2}}$$\n",
+    "\n",
+    "First define variables with:\n",
+    "\n",
+    "```python\n",
+    "sym.var('x, sigma, mu')\n",
+    "```"
    ]
   },
   {
@@ -525,6 +524,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
+    "# define variables\n",
     "expr = \n",
     "expr #displays expression"
    ]

book/08/asserts.ipynb book/09/asserts.ipynbbook/08/asserts.ipynb renamed to book/09/asserts.ipynb

@@ -42,14 +42,16 @@ parts:
       sections:
       - file: 07/Exercises/01.ipynb
       - file: 07/Exercises/bug_report.md 
-    - file: 08/intro.md
-      title: 8. Errors
+    - file: 08/sympy
+      title: 8. SymPy
+    - file: 09/intro.md
+      title: 9. Errors
       sections:
-      - file: 08/error_types.ipynb
-      - file: 08/traceback.ipynb
-      - file: 08/raise_errors.ipynb
-      - file: 08/handling_errors.ipynb
-      - file: 08/asserts.ipynb
+      - file: 09/error_types.ipynb
+      - file: 09/traceback.ipynb
+      - file: 09/raise_errors.ipynb
+      - file: 09/handling_errors.ipynb
+      - file: 09/asserts.ipynb
   - caption: End of course survey
     chapters:
     - file: End-of-course-survey.md

book/08/error_types.ipynb book/09/error_types.ipynbbook/08/error_types.ipynb renamed to book/09/error_types.ipynb

@@ -1,6 +1,3 @@
----
----
-
 @inproceedings{holdgraf_evidence_2014,
 	address = {Brisbane, Australia, Australia},
 	title = {Evidence for {Predictive} {Coding} in {Human} {Auditory} {Cortex}},
@@ -54,3 +51,17 @@ @book{ruby
   year      = {2008},
   publisher = {O'Reilly Media}
 }
+
+@misc{sympy_why,
+  title={Sympy documentation},
+  author={{SymPy Development Team}},
+  howpublished={\url{https://docs.sympy.org/latest/tutorials/intro-tutorial/intro.html}},
+  year={2023}
+}
+
+@misc{jason_moore,
+  title={Learn Multibody Dynamics, SymPy},
+  author={Moore, Jason},
+  howpublished={\url{https://moorepants.github.io/learn-multibody-dynamics/sympy.html}},
+  year={2023}
+}