### Install PyMeeus via pip

Source: https://pymeeus.readthedocs.io/en/latest/index.html

Standard installation commands for the PyMeeus library.

```bash
pip install pymeeus
```

```bash
pip install --user pymeeus
```

```bash
pip3 install --user pymeeus
```

```bash
pip3 install -U pymeeus
```

--------------------------------

### Angle Class Initialization

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Angle.html

Example of creating an Angle object using degrees, minutes, and seconds.

```python
a = Angle(-23.0, 26.0, 48.999983999)
print("a = Angle(-23.0, 26.0, 48.999983999)")
```

--------------------------------

### Corrected Script Implementation

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-General.html

The corrected version of the initial example using the 'from' import statement.

```python
from pymeeus.Epoch import Epoch

mydate = Epoch(1992, 10, 13.0)
```

--------------------------------

### Mars Class Usage Examples

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Mars.html

Comprehensive example showing how to compute heliocentric and geocentric positions for Mars.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's show some uses of Mars class
    print("\n" + 35 * "*")
    print("*** Use of Mars class")
    print(35 * "*" + "\n")

    # Let's now compute the heliocentric position for a given epoch
    epoch = Epoch(2018, 10, 27.0)
    lon, lat, r = Mars.geometric_heliocentric_position(epoch)
    print_me("Geometric Heliocentric Longitude", lon.to_positive())
    print_me("Geometric Heliocentric Latitude", lat)
    print_me("Radius vector", r)

    print("")

    # Compute the geocentric position for 1992/12/20:
    epoch = Epoch(1992, 12, 20.0)
    ra, dec, elon = Mars.geocentric_position(epoch)
    print_me("Right ascension", ra.ra_str(n_dec=1))
    print_me("Declination", dec.dms_str(n_dec=1))
    print_me("Elongation", elon.dms_str(n_dec=1))

    print("")
```

--------------------------------

### Perform astronomical date calculations

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Epoch.html

Comprehensive example demonstrating Epoch instantiation, calendar utilities, and leap second lookups.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's do some work with the Epoch class
    print("\n" + 35 * "*")
    print("*** Use of Epoch class")
    print(35 * "*" + "\n")

    e = Epoch(1987, 6, 19.5)
    print_me("JDE for 1987/6/19.5", e)

    # Redefine the Epoch object
    e.set(333, "Jan", 27, 12)
    print_me("JDE for 333/1/27.5", e)

    # We can create an Epoch from a 'date' or 'datetime' object
    d = datetime.datetime(837, 4, 10, 7, 12, 0, 0)
    f = Epoch(d)
    print_me("JDE for 837/4/10.3", f)

    print("")

    # Check if a given date belong to the Julian or Gregorian calendar
    print_me("Is 1590/4/21.4 a Julian date?", Epoch.is_julian(1590, 4, 21.4))

    print("")

    # We can also check if a given year is leap or not
    print_me("Is -1000 a leap year?", Epoch.is_leap(-1000))
    print_me("Is 1800 a leap year?", Epoch.is_leap(1800))
    print_me("Is 2012 a leap year?", Epoch.is_leap(2012))

    print("")

    # Get the Day Of Year corresponding to a given date
    print_me("Day Of Year (DOY) of 1978/11/14", Epoch.get_doy(1978, 11, 14))
    print_me("Day Of Year (DOY) of -400/2/29.9", Epoch.get_doy(-400, 2, 29.9))
    # As before, but using the contents of the Epoch object
    e = Epoch(2017, 12, 31.7)
    print_me("Day Of Year (DOY) of 2017/12/31.7", round(e.doy(), 1))

    print("")

    # Now the opposite: Get a date from a DOY
    t = Epoch.doy2date(2017, 365.7)
    s = str(t[0]) + "/" + str(t[1]) + "/" + str(round(t[2], 2))
    print_me("Date from DOY 2017:365.7", s)

    t = Epoch.doy2date(-4, 60)
    s = str(t[0]) + "/" + str(t[1]) + "/" + str(round(t[2], 2))
    print_me("Date from DOY -4:60", s)

    print("")

    # There is an internal table which we can use to get the leap seconds
    print_me("Number of leap seconds applied up to July 1983",
             Epoch.leap_seconds(1983, 7))

    print("")

    # We can convert the internal JDE value back to a date
    e = Epoch(2436116.31)
    y, m, d = e.get_date()
    s = str(y) + "/" + str(m) + "/" + str(round(d, 2))
    print_me("Date from JDE 2436116.31", s)

    print("")
```

--------------------------------

### Demonstrate Neptune Class Usage

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Neptune.html

Example script showing how to compute heliocentric and geocentric positions for Neptune.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's show some uses of Neptune class
    print("\n" + 35 * "*")
    print("*** Use of Neptune class")
    print(35 * "*" + "\n")

    # Let's now compute the heliocentric position for a given epoch
    epoch = Epoch(2018, 10, 27.0)
    lon, lat, r = Neptune.geometric_heliocentric_position(epoch)
    print_me("Geometric Heliocentric Longitude", lon.to_positive())
    print_me("Geometric Heliocentric Latitude", lat)
    print_me("Radius vector", r)

    print("")

    # Compute the geocentric position for 1992/12/20:
    epoch = Epoch(1992, 12, 20.0)
    ra, dec, elon = Neptune.geocentric_position(epoch)
    print_me("Right ascension", ra.ra_str(n_dec=1))
    print_me("Declination", dec.dms_str(n_dec=1))
    print_me("Elongation", elon.dms_str(n_dec=1))
```

--------------------------------

### Interpolation Class Usage Examples

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Interpolation.html

Demonstrates initializing the Interpolation class, using the copy constructor, performing interpolation, and calculating derivatives and roots.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's now work with the Interpolation class
    print("\n" + 35 * "*")
    print("*** Use of Interpolation class")
    print(35 * "*" + "\n")

    i = Interpolation([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
    print("i = Interpolation([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])")
    print(i)
    print("NOTE:")
    print("   a. They are ordered in 'x'")
    print("   b. The extra value in 'x' was dropped")

    print("")

    # Use the copy constructor
    print("We can easily make a copy of an Interpolation object")
    j = Interpolation(i)
    print("j = Interpolation(i)")
    print(j)

    print("")

    # Get the number of interpolation points stored
    print_me("Number or interpolation points in 'j'", len(j))  # 6

    print("")

    j = Interpolation([0.0, 1.0, 3.0], [-1.0, -2.0, 2.0])
    print("j = Interpolation([0.0, 1.0, 3.0], [-1.0, -2.0, 2.0])")
    print(j)
    print_me("j(2)", j(2))
    print_me("j(0.5)", j(0.5))
    # Test with a value already in the data table
    print_me("j(1)", j(1))

    print("")

    # We can interpolate Angles too
    k = Interpolation(
        [27.0, 27.5, 28.0, 28.5, 29.0],
        [
            Angle(0, 54, 36.125),
            Angle(0, 54, 24.606),
            Angle(0, 54, 15.486),
            Angle(0, 54, 8.694),
            Angle(0, 54, 4.133),
        ],
    )
    print(
        "k = Interpolation([27.0, 27.5, 28.0, 28.5, 29.0],\n\
                      [Angle(0, 54, 36.125), Angle(0, 54, 24.606),\n\
                       Angle(0, 54, 15.486), Angle(0, 54, 8.694),\n\
                       Angle(0, 54, 4.133)])"
    )

    print_me("k(28.278)", Angle(k(28.278)).dms_str())

    print("")

    m = Interpolation([-1.0, 0.0, 1.0], [-2.0, 3.0, 2.0])
    print("m = Interpolation([-1.0, 0.0, 1.0], [-2.0, 3.0, 2.0])")
    print(m)
    # Get interpolated values
    print_me("m(-0.5)", m(-0.5))
    print_me("m(0.5)", m(0.5))
    # Get derivatives
    print_me("m'(-1.0)", m.derivative(-1.0))
    print_me("m'(-0.5)", m.derivative(-0.5))
    print_me("m'(0.0)", m.derivative(0.0))
    print_me("m'(0.5)", m.derivative(0.5))
    print_me("m'(1.0)", m.derivative(1.0))
    # Get the root within the interval
    print_me("m.root()", m.root())
    # Get the extremum within the interval
    print_me("m.minmax()", m.minmax())

    m = Interpolation(
        [29.43, 30.97, 27.69, 28.11, 31.58, 33.05],
        [
            0.4913598528,
            0.5145891926,
            0.4646875083,
            0.4711658342,
            0.5236885653,
            0.5453707057,
        ],
    )

    print_me("sin(29.5)\t", m(29.5))
    print_me("sin(30.0)\t", m(30.0))
    print_me("sin(30.5)\t", m(30.5))
    # Derivative must be adjusted because degrees were used instead of radians
    print_me("sin'(29.5)\t", degrees(m.derivative(29.5)))
    print_me("sin'(30.0)\t", degrees(m.derivative(30.0)))
    print_me("sqrt(3.0)/2.0\t", sqrt(3.0) / 2.0)
    print_me("sin'(30.5)\t", degrees(m.derivative(30.5)))


if __name__ == "__main__":

    main()
```

--------------------------------

### Demonstrate Saturn Class Usage

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Saturn.html

Example script showing how to compute heliocentric and geocentric positions for specific epochs.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's show some uses of Saturn class
    print("\n" + 35 * "*")
    print("*** Use of Saturn class")
    print(35 * "*" + "\n")

    # Let's now compute the heliocentric position for a given epoch
    epoch = Epoch(2018, 10, 27.0)
    lon, lat, r = Saturn.geometric_heliocentric_position(epoch)
    print_me("Geometric Heliocentric Longitude", lon.to_positive())
    print_me("Geometric Heliocentric Latitude", lat)
    print_me("Radius vector", r)

    print("")

    # Compute the geocentric position for 1992/12/20:
    epoch = Epoch(1992, 12, 20.0)
    ra, dec, elon = Saturn.geocentric_position(epoch)
    print_me("Right ascension", ra.ra_str(n_dec=1))
    print_me("Declination", dec.dms_str(n_dec=1))
    print_me("Elongation", elon.dms_str(n_dec=1))

    print("")
```

--------------------------------

### Traceback Error Example

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-General.html

The error message generated when attempting to access a class directly from the library root.

```text
Traceback (most recent call last):
  File "/home/user/test/test.py", line 3, in <module>
    epoch = pymeeus.Epoch(1992, 10, 13.0)
AttributeError: module 'pymeeus' has no attribute 'Epoch'
```

--------------------------------

### Calculate planet alignment with stars

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Coordinates.html

Example usage of planet_stars_in_line to determine alignment of celestial bodies.

```python
>>> alpha_1 = Angle( 7, 55, 55.36, ra=True)
>>> delta_1 = Angle(21, 41,  3.0)
>>> alpha_2 = Angle( 7, 58, 22.55, ra=True)
>>> delta_2 = Angle(21, 35, 23.4)
>>> alpha_3 = Angle( 8,  0, 48.99, ra=True)
>>> delta_3 = Angle(21, 29, 38.2)
>>> alpha_4 = Angle( 8,  3, 14.66, ra=True)
>>> delta_4 = Angle(21, 23, 47.5)
>>> alpha_5 = Angle( 8,  5, 39.54, ra=True)
>>> delta_5 = Angle(21, 17, 51.4)
>>> alpha_star1 = Angle( 7, 34, 16.40, ra=True)
>>> delta_star1 = Angle(31, 53, 51.2)
>>> alpha_star2 = Angle( 7, 45,  0.10, ra=True)
>>> delta_star2 = Angle(28,  2, 12.5)
>>> alpha_list = [alpha_1, alpha_2, alpha_3, alpha_4, alpha_5]
>>> delta_list = [delta_1, delta_2, delta_3, delta_4, delta_5]
>>> n = planet_stars_in_line(alpha_list, delta_list, alpha_star1, \
                             delta_star1, alpha_star2, delta_star2)
>>> print(round(n, 4))
0.2233
```

--------------------------------

### Find Extremum with Interpolation

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Interpolation.html

Example usage of the minmax method to find the extremum of an interpolated function.

```python
>>> m = Interpolation([-1.0, 0.0, 1.0], [-2.0, 3.0, 2.0])
>>> round(m.minmax(), 8)
0.33333333
```

--------------------------------

### Jupiter Class Usage Examples

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Jupiter.html

A comprehensive script demonstrating various calculations including heliocentric/geocentric positions, orbital elements, and conjunction dates.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's show some uses of Jupiter class
    print("\n" + 35 * "*")
    print("*** Use of Jupiter class")
    print(35 * "*" + "\n")

    # Let's now compute the heliocentric position for a given epoch
    epoch = Epoch(2018, 10, 27.0)
    lon, lat, r = Jupiter.geometric_heliocentric_position(epoch)
    print_me("Geometric Heliocentric Longitude", lon.to_positive())
    print_me("Geometric Heliocentric Latitude", lat)
    print_me("Radius vector", r)

    print("")

    # Compute the geocentric position for 1992/12/20:
    epoch = Epoch(1992, 12, 20.0)
    ra, dec, elon = Jupiter.geocentric_position(epoch)
    print_me("Right ascension", ra.ra_str(n_dec=1))
    print_me("Declination", dec.dms_str(n_dec=1))
    print_me("Elongation", elon.dms_str(n_dec=1))

    print("")

    # Print mean orbital elements for Jupiter at 2065.6.24
    epoch = Epoch(2065, 6, 24.0)
    l, a, e, i, ome, arg = Jupiter.orbital_elements_mean_equinox(epoch)
    print_me("Mean longitude of the planet", round(l, 6))       # 222.433723
    print_me("Semimajor axis of the orbit (UA)", round(a, 8))   # 5.20260333
    print_me("Eccentricity of the orbit", round(e, 7))          # 0.0486046
    print_me("Inclination on plane of the ecliptic", round(i, 6))   # 1.29967
    print_me("Longitude of the ascending node", round(ome, 5))  # 101.13309
    print_me("Argument of the perihelion", round(arg, 6))       # -85.745532

    print("")

    # Compute the time of the conjunction close to 1993/10/1
    epoch = Epoch(1993, 10, 1.0)
    conj = Jupiter.conjunction(epoch)
    y, m, d = conj.get_date()
    d = round(d, 4)
    date = "{}/{}/{}".format(y, m, d)
    print_me("Conjunction date", date)
```

--------------------------------

### Module Execution Entry Point

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/base.html

Demonstrates the usage of the module's utility functions and constants.

```python
def main():

    # Let's define a small helper function
    def print_me(msg, val):
        print("{}: {}".format(msg, val))

    # Let's print the tolerance
    print_me("The default value for the tolerance is", TOL)

    # Find the accuracy of this computer
    j, d = machine_accuracy()
    print_me("Number of significant BITS in the mantissa\t", j)
    print_me("Number of significant DIGITS in a decimal number", d)

    print("")

    print_me("The suffix for ordinal 2 is", get_ordinal_suffix(2))
    print_me("The suffix for ordinal 11 is", get_ordinal_suffix(11))
    print_me("The suffix for ordinal 12 is", get_ordinal_suffix(12))
    print_me("The suffix for ordinal 13 is", get_ordinal_suffix(13))
    print_me("The suffix for ordinal 14 is", get_ordinal_suffix(14))
    print_me("The suffix for ordinal 16 is", get_ordinal_suffix(16))
    print_me("The suffix for ordinal 23 is", get_ordinal_suffix(23))


if __name__ == "__main__":

    main()
```

--------------------------------

### Angle Initialization and Basic Output

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Angle.html

Demonstrates creating Angle objects and printing them using different methods.

```python
# First we print using the __call__ method (note the extra parentheses)
print_me("The angle 'a()' is", a())  # -23.44694444

# Second we print using the __str__ method (no extra parentheses needed)
print_me("The angle 'a' is", a)  # -23.44694444

print("")

# Use the copy constructor
b = Angle(a)
print_me("Angle 'b', which is a copy of 'a', is", b)
```

--------------------------------

### Calculate Geometric Heliocentric Position

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Uranus.html

Example usage of the geometric_heliocentric_position method.

```python
>>> epoch = Epoch(2018, 10, 27.0)
>>> l, b, r = Uranus.geometric_heliocentric_position(epoch)
>>> print(round(l.to_positive(), 4))
30.5888
>>> print(round(b, 4))
-0.5315
>>> print(round(r, 5))
19.86964
```

--------------------------------

### Sun.beginning_synodic_rotation

Source: https://pymeeus.readthedocs.io/en/latest/bodies/Sun.html

Calculates the epoch when the Carrington’s synodic rotation starts.

```APIDOC
## Sun.beginning_synodic_rotation(number)

### Description
Calculates the epoch when the Carrington’s synodic rotation No. 'number' starts.

### Parameters
- **number** (int) - Required - Number of Carrington’s synodic rotation.

### Returns
- **Epoch** - Epoch when the provided rotation starts.
```

--------------------------------

### Generate HTML Documentation

Source: https://pymeeus.readthedocs.io/en/latest/index.html

Command to build the project documentation locally using Sphinx.

```bash
make html
```

--------------------------------

### Get Object Representation

Source: https://pymeeus.readthedocs.io/en/latest/core/CurveFitting.html

Provides a string representation that can be used to recreate the object.

```python
>>> i = CurveFitting([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
>>> repr(i)
'CurveFitting([5, 3, 6, 1, 2, 4], [10, 6, 12, 2, 4, 8])'
```

--------------------------------

### Incorrect Library Import Pattern

Source: https://pymeeus.readthedocs.io/en/latest/index.html

Example of an incorrect import attempt that results in an AttributeError.

```python
import pymeeus

mydate = pymeeus.Epoch(1992, 10, 13.0)
```

```text
Traceback (most recent call last):
  File "/home/user/test/test.py", line 3, in <module>
    epoch = pymeeus.Epoch(1992, 10, 13.0)
AttributeError: module 'pymeeus' has no attribute 'Epoch'
```

--------------------------------

### Perform Quadratic Curve Fitting

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/CurveFitting.html

Demonstrates how to initialize the CurveFitting class with data points and calculate quadratic coefficients.

```python
>>> cf2 = CurveFitting([-2.0, -1.5, -1.0, -0.5, 0.0, 0.5, 1.0, 1.5,
...                     2.0, 2.5,3.0],
...                    [-9.372, -3.821, 0.291, 3.730, 5.822, 8.324,
...                     9.083, 6.957, 7.006, 0.365, -1.722])
>>> a, b, c = cf2.quadratic_fitting()
>>> print("a = {}; b = {}; c = {}".format(round(a, 2), round(b, 2),
...                                       round(c, 2)))
a = -2.22; b = 3.76; c = 6.64
```

--------------------------------

### Initialize CurveFitting with various input formats

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/CurveFitting.html

Demonstrates initializing the CurveFitting class using different input structures such as lists, sequences, and existing objects.

```python
>>> i = CurveFitting([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
>>> print(i._x)
[5, 3, 6, 1, 2, 4]
>>> print(i._y)
[10, 6, 12, 2, 4, 8]
>>> j = CurveFitting([3, -8, 1, 12, 2, 5, 8])
>>> print(j._x)
[0, 1, 2, 3, 4, 5, 6]
>>> print(j._y)
[3, -8, 1, 12, 2, 5, 8]
>>> k = CurveFitting(3, -8, 1, 12, 2, 5, 8)
>>> print(k._x)
[3, 1, 2]
>>> print(k._y)
[-8, 12, 5]
>>> m = CurveFitting(k)
>>> print(m._x)
[3, 1, 2]
>>> print(m._y)
[-8, 12, 5]
```

--------------------------------

### Get Number of Data Pairs

Source: https://pymeeus.readthedocs.io/en/latest/core/CurveFitting.html

Returns the count of value pairs stored in the object.

```python
>>> i = CurveFitting([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
>>> len(i)
6
```

--------------------------------

### Radians and Right Ascension Handling

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Angle.html

Shows how to initialize angles with radians or Right Ascension and perform conversions.

```python
# We can define the angle as in radians. It will be converted to degrees
b = Angle(pi, radians=True)
print_me("b = Angle(pi, radians=True); print(b)", b)  # 180.0

# And we can easily carry out the 'degrees to radians' conversion
print_me("print(b.rad())", b.rad())  # 3.14159265359

print("")

# We can also specify the angle as a Right Ascension
print("Angle can be given as a Right Ascension: Hours, Minutes, Seconds")
a.set_ra(9, 14, 55.8)
print("a.set_ra(9, 14, 55.8)")
print_me("   print(a)", a)
b = Angle(9, 14, 55.8, ra=True)
print("b = Angle(9, 14, 55.8, ra=True)")
print_me("   print(b)", b)

print("")

# We can print the Angle as Right Ascension, as a float and as string
a = Angle(138.75)
print("a = Angle(138.75)")
print_me("   print(a.get_ra())", a.get_ra())
print_me("   print(a.ra_str())", a.ra_str())
print_me("   print(a.ra_str(False))", a.ra_str(False))
```

--------------------------------

### Initialize and Print Angle Objects

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Angle.html

Demonstrates creating an Angle object from sexagesimal components and copying an existing Angle instance.

```python
>>> a = Angle(-13, 30, 0.0)
>>> print(a)
-13.5
>>> b = Angle(a)
>>> print(b)
-13.5
```

--------------------------------

### Perform Linear and Quadratic Curve Fitting

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/CurveFitting.html

Demonstrates initializing a CurveFitting object, performing linear regression, using the copy constructor, and executing quadratic fitting on a dataset.

```python
cf1 = CurveFitting(
    [
        73.0,
        38.0,
        35.0,
        42.0,
        78.0,
        68.0,
        74.0,
        42.0,
        52.0,
        54.0,
        39.0,
        61.0,
        42.0,
        49.0,
        50.0,
        62.0,
        44.0,
        39.0,
        43.0,
        54.0,
        44.0,
        37.0,
    ],
    [
        90.4,
        125.3,
        161.8,
        143.4,
        52.5,
        50.8,
        71.5,
        152.8,
        131.3,
        98.5,
        144.8,
        78.1,
        89.5,
        63.9,
        112.1,
        82.0,
        119.8,
        161.2,
        208.4,
        111.6,
        167.1,
        162.1,
    ],
)

# Let's use 'linear_fitting()'
a, b = cf1.linear_fitting()
print("Linear fitting for cf1:")
print("   a = {}\tb = {}".format(round(a, 2), round(b, 2)))

print("")

# Use the copy constructor
print("Let's make a copy:")
cf2 = CurveFitting(cf1)
print("   cf2 = CurveFitting(cf1)")
a, b = cf2.linear_fitting()
print("Linear fitting for cf2:")
print("   a = {}\tb = {}".format(round(a, 2), round(b, 2)))

print("")

# Get the number of value pairs internally stored
print_me("Number of value pairs inside 'cf2'", len(cf2))  # 22

print("")

# Compute the correlation coefficient
r = cf1.correlation_coeff()
print("Correlation coefficient:")
print_me("   r", round(r, 3))

cf2 = CurveFitting(
    [-2.0, -1.5, -1.0, -0.5, 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0],
    [
        -9.372,
        -3.821,
        0.291,
        3.730,
        5.822,
        8.324,
        9.083,
        6.957,
        7.006,
        0.365,
        -1.722,
    ],
)

print("")

# Now use 'quadratic_fitting()'
a, b, c = cf2.quadratic_fitting()
# Original curve: y = -2.0*x*x + 3.5*x + 7.0 + noise
print("Quadratic fitting:")
print("   a = {}\tb = {}\tc = {}".format(round(a, 2), round(b, 2),
                                         round(c, 2)))
```

--------------------------------

### Get Interpolation Point Count

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Interpolation.html

Returns the number of interpolation points currently stored in the object.

```python
>>> i = Interpolation([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
>>> len(i)
6
```

--------------------------------

### Calculate Topocentric Coordinates

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Earth.html

Example usage of the parallax_ecliptical method to convert geocentric coordinates to topocentric ones.

```python
>>> longitude = Angle(181, 46, 22.5)
>>> latitude = Angle(2, 17, 26.2)
>>> semidiameter = Angle(0, 16, 15.5)
>>> obs_lat = Angle(50, 5, 7.8)
>>> obliquity = Angle(23, 28, 0.8)
>>> sidereal_time = Angle(209, 46, 7.9)
>>> distance = 0.0024650163
>>> topo_lon, topo_lat, topo_diam = \
        Earth.parallax_ecliptical(longitude, latitude, semidiameter, \
                                  obs_lat, obliquity, sidereal_time, \
                                  distance)
>>> print(topo_lon.dms_str(n_dec=1))
181d 48' 5.0''
>>> print(topo_lat.dms_str(n_dec=1))
1d 29' 7.1''
>>> print(topo_diam.dms_str(n_dec=1))
16' 25.5''
```

--------------------------------

### Initialize quadratic fitting object

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-CurveFitting.html

Create a CurveFitting object with data for quadratic regression.

```python
cf2 = CurveFitting([-2.0, -1.5, -1.0, -0.5, 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0],

                   [-9.372, -3.821, 0.291, 3.730, 5.822, 8.324, 9.083,

                    6.957, 7.006, 0.365, -1.722])
```

--------------------------------

### Calculate Jupiter's position

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/JupiterMoons.html

Example usage for calculating the distance and position of Jupiter relative to an epoch.

```python
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> delta, tau, l, b, r = JupiterMoons.calculate_delta( \
utc_1992_12_16_00_00_00)
>>> print(round(delta, 10))
5.6611211815
>>> print(round(tau, 10))
0.032695909
```

--------------------------------

### Correct Module Import Patterns

Source: https://pymeeus.readthedocs.io/en/latest/index.html

Demonstrates the correct way to import specific modules and components from the PyMeeus library.

```python
import pymeeus.Angle
```

```python
import pymeeus.Angle

i = pymeeus.Angle.Angle(11.94524)
```

```python
from pymeeus.Angle import Angle
from pymeeus.Epoch import Epoch, JDE2000
from math import sin, cos, tan, acos, atan2, sqrt, radians, log10
```

```python
from pymeeus.Epoch import Epoch

mydate = Epoch(1992, 10, 13.0)
```

--------------------------------

### Creating Epoch from datetime

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-Epoch.html

Shows how to initialize an Epoch object using a standard Python datetime object.

```python
d = datetime.datetime(837, 4, 10, 7, 12, 0, 0)

f = Epoch(d)

print_me("JDE for 837/4/10.3", f)
```

--------------------------------

### Compute Jupiter Conjunction Time

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Jupiter.html

Example usage of the conjunction method to find the time of conjunction for a given epoch.

```python
>>> epoch = Epoch(1993, 10, 1.0)
        >>> conj = Jupiter.conjunction(epoch)
        >>> y, m, d = conj.get_date()
        >>> print(y)
        1993
        >>> print(m)
        10
        >>> print(round(d, 4))
        18.3341
```

--------------------------------

### Retrieving interpolation point count

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-Interpolation.html

Uses the len() function to get the number of points stored in the interpolation object.

```python
print_me("Number or interpolation points in 'j'", len(j))

# Number or interpolation points in 'j': 3
```

--------------------------------

### Working with radians

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-Angle.html

Initializing an Angle from radians and converting back to radians.

```python
b = Angle(pi, radians=True)

print_me("b = Angle(pi, radians=True); print(b)", b)

# b = Angle(pi, radians=True); print(b): 180.0
```

```python
print_me("print(b.rad())", b.rad())

# print(b.rad()): 3.14159265359
```

--------------------------------

### Initialize CurveFitting data

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/CurveFitting.html

Demonstrates how to initialize the CurveFitting object using different input formats such as lists, tuples, or individual arguments.

```python
>>> i = CurveFitting()
>>> i.set([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
>>> print(i._x)
[5, 3, 6, 1, 2, 4]
>>> print(i._y)
[10, 6, 12, 2, 4, 8]
>>> j = CurveFitting()
>>> j.set([3, -8, 1, 12, 2, 5, 8])
>>> print(j._x)
[0, 1, 2, 3, 4, 5, 6]
>>> print(j._y)
[3, -8, 1, 12, 2, 5, 8]
>>> k = CurveFitting(3, -8, 1, 12, 2, 5, 8)
>>> print(k._x)
[3, 1, 2]
>>> print(k._y)
[-8, 12, 5]
```

--------------------------------

### Get Ordinal Suffix

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/base.html

Returns the English ordinal suffix (st, nd, rd, th) for a given number.

```python
def get_ordinal_suffix(ordinal):
    """Method to get the suffix of a given ordinal number, like 1'st',
    2'nd', 15'th', etc.

    :param ordinal: Ordinal number
    :type ordinal: int

    :returns: Suffix corresponding to input ordinal number
    :rtype: str
    :raises: TypeError if input type is invalid.

    >>> get_ordinal_suffix(40)
    'th'
    >>> get_ordinal_suffix(101)
    'st'
    >>> get_ordinal_suffix(2)
    'nd'
    >>> get_ordinal_suffix(19)
    'th'
    >>> get_ordinal_suffix(23)
    'rd'
    """

    if not isinstance(ordinal, (int, float)):
        raise TypeError("Invalid input type")
    else:
        ordinal = int(floor(ordinal))
        unit = ordinal % 10
        if unit == 1 and ordinal != 11:
            return "st"
        elif unit == 2 and ordinal != 12:
            return "nd"
        elif unit == 3 and ordinal != 13:
            return "rd"
        else:
            return "th"
```

--------------------------------

### Interpolation object initialization

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-Interpolation.html

Demonstrates creating an Interpolation object. Note that input data is automatically ordered by x-values and extra values may be dropped.

```python
i = Interpolation([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])

print(i)

# X: [1, 2, 3, 4, 5, 6]

# Y: [2, 4, 6, 8, 10, 12]
```

--------------------------------

### Get official string representation

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Interpolation.html

Demonstrates the official string representation of an Interpolation instance that can be used to recreate the object.

```python
>>> i = Interpolation([5, 3, 6, 1, 2, 4, 9], [10, 6, 12, 2, 4, 8])
>>> repr(i)
'Interpolation([1, 2, 3, 4, 5, 6], [2, 4, 6, 8, 10, 12])'
```

--------------------------------

### Calculate parallax correction for equatorial coordinates

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Earth.html

Example usage of the parallax_correction method to adjust geocentric coordinates to topocentric coordinates.

```python
>>> right_ascension = Angle(22, 38, 7.25, ra=True)
>>> declination = Angle(-15, 46, 15.9)
>>> latitude = Angle(33, 21, 22)
>>> distance = 0.37276
>>> hour_angle = Angle(288.7958)
>>> topo_ra, topo_dec = Earth.parallax_correction(right_ascension, 
                                                          declination, 
                                                          latitude, distance, 
                                                          hour_angle)
>>> print(topo_ra.ra_str(n_dec=2))
22h 38' 8.54''
>>> print(topo_dec.dms_str(n_dec=1))
-15d 46' 30.0''
```

--------------------------------

### Creating and setting Epoch objects

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-Epoch.html

Demonstrates initializing an Epoch object with specific dates and updating it using the set method.

```python
e = Epoch(1987, 6, 19.5)

print_me("JDE for 1987/6/19.5", e)
```

```python
e.set(333, 'Jan', 27, 12)

print_me("JDE for 333/1/27.5", e)
```

--------------------------------

### Compute Uranus Conjunction Time

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Uranus.html

Example usage of the conjunction method to find the time of conjunction closest to a given epoch.

```python
>>> epoch = Epoch(1993, 10, 1.0)
        >>> conj = Uranus.conjunction(epoch)
        >>> y, m, d = conj.get_date()
        >>> print(y)
        1994
        >>> print(m)
        1
        >>> print(round(d, 4))
        12.7365
```

--------------------------------

### Comparison and Addition

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Angle.html

Demonstrates comparison operators and adding angles or numbers.

```python
# Comparison operators
print_me("   d == e", d == e)  # False
print_me("   d != e", d != e)  # True
print_me("   d > e", d > e)  # True
print_me("   c >= 180.0", c >= 180.0)  # False
print_me("   c < 180.0", c < 180.0)  # True
print_me("   c <= 180.0", c <= 180.0)  # True

print("")

# It is very easy to add Angles to obtain a new Angle
e = c + d
print_me("   c + d", e)  # 133.7825

# We can also directly add a decimal angle
e = c + 11.5
print_me("   c + 11.5", e)  # 150.2325

print("")

# Types allowed are int, float and Angle
print('e = c + "32.5"')
try:
    e = c + "32.5"
except TypeError:
    print("TypeError!: Valid types are int, float, and Angle, not string!")
```

--------------------------------

### Calculate Inferior Conjunction

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Venus.html

Example usage of the inferior_conjunction method to find the time of the inferior conjunction closest to a provided epoch.

```python
>>> epoch = Epoch(1882, 12, 1.0)
>>> conjunction = Venus.inferior_conjunction(epoch)
>>> y, m, d = conjunction.get_date()
>>> print(y)
1882
>>> print(m)
12
>>> print(round(d, 1))
6.7
```

--------------------------------

### Initialize CurveFitting object

Source: https://pymeeus.readthedocs.io/en/latest/examples/ex-CurveFitting.html

Create a CurveFitting instance with provided x and y data points.

```python
cf1 = CurveFitting([73.0, 38.0, 35.0, 42.0, 78.0, 68.0, 74.0, 42.0, 52.0,

                    54.0, 39.0, 61.0, 42.0, 49.0, 50.0, 62.0, 44.0, 39.0,

                    43.0, 54.0, 44.0, 37.0],

                   [90.4, 125.3, 161.8, 143.4, 52.5, 50.8, 71.5, 152.8,

                    131.3, 98.5, 144.8, 78.1, 89.5, 63.9, 112.1, 82.0,

                    119.8, 161.2, 208.4, 111.6, 167.1, 162.1])
```

--------------------------------

### Compute Moon Librations

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Moon.html

Example usage of the moon_librations method to calculate optical, physical, and total librations for a given epoch.

```python
>>> epoch = Epoch(1992, 4, 12.0)
>>> lopt, bopt, lphys, bphys, ltot, btot = Moon.moon_librations(epoch)
>>> print(round(lopt, 3))
-1.206
>>> print(round(bopt, 3))
4.194
>>> print(round(lphys, 3))
-0.025
>>> print(round(bphys, 3))
0.006
>>> print(round(ltot, 2))
-1.23
>>> print(round(btot, 3))
4.2
```

--------------------------------

### Calculate Neptune Conjunction Time

Source: https://pymeeus.readthedocs.io/en/latest/_modules/pymeeus/Neptune.html

Example usage of the conjunction method to find the time of the conjunction closest to a given epoch.

```python
>>> epoch = Epoch(1993, 10, 1.0)
>>> conj = Neptune.conjunction(epoch)
>>> y, m, d = conj.get_date()
>>> print(y)
1994
>>> print(m)
1
>>> print(round(d, 4))
11.3057
```