6. Plotting og grafikk

Plotting

Oppgave 1

import matplotlib.pyplot as plt
import numpy as np

def f(x):
    return x**3 - 2*x**2 + x + 3

x = np.linspace(-2, 3, 1000)
y = f(x)

plt.plot(x, y, label="f(x)")
plt.grid()
plt.axhline(0)
plt.axvline(0)
plt.xlabel("x")
plt.ylabel("f(x)")
plt.legend()
plt.show()

Oppgave 2

import numpy as np
import matplotlib.pyplot as plt

def f(x):
    return x**2 - 2

def g(x):
    return x + 1

def h(x):
    return 1/x

x = np.linspace(-3, 3, 1000)
y1 = f(x)
y2 = g(x)
y3 = h(x)

plt.plot(x, y1, label="f(x)")
plt.plot(x, y2, label="g(x)")
plt.plot(x, y3, label="h(x)")
plt.grid()
plt.axhline(0)
plt.axvline(0)
plt.xlabel("x")
plt.ylabel("y")
plt.legend()
plt.ylim([-20, 20])
plt.show()

Oppgave 3

a) Bilen kjører først noen sekunder i om lag 30 km/t, deretter akselererer den en del, og kjører noen sekunder i om lag 50 km/t.

b)

import matplotlib.pyplot as plt

v = [30,34,32,33,30,30,29,28,45,49,50,50,50,54,50,51]
t = [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]

plt.plot(t, v, label="v(t)")
plt.grid()
plt.axhline(0, c="k")
plt.axvline(0, c="k")
plt.xlabel("x")
plt.ylabel("v(t)")
plt.legend()
plt.show()

c) Løsningen på denne deloppgaven er ikke testet

import numpy as np

data = np.loadtxt("../datasett/bevegelse.txt")
v = data[:,0]
t = data[:,1]

plt.plot(t, v, label="v(t)")
plt.grid()
plt.axhline(0, c="k")
plt.axvline(0, c="k")
plt.xlabel("x")
plt.ylabel("v(t)")
plt.legend()
plt.show()

---------------------------------------------------------------------------
OSError                                   Traceback (most recent call last)
<ipython-input-16-9df7d2601c93> in <module>
      1 import numpy as np
      2 
----> 3 data = np.loadtxt("../datasett/bevegelse.txt")
      4 v = data[:,0]
      5 t = data[:,1]

~/.pyenv/versions/3.8.2/envs/profag/lib/python3.8/site-packages/numpy/lib/npyio.py in loadtxt(fname, dtype, comments, delimiter, converters, skiprows, usecols, unpack, ndmin, encoding, max_rows)
    959             fname = os_fspath(fname)
    960         if _is_string_like(fname):
--> 961             fh = np.lib._datasource.open(fname, 'rt', encoding=encoding)
    962             fencoding = getattr(fh, 'encoding', 'latin1')
    963             fh = iter(fh)

~/.pyenv/versions/3.8.2/envs/profag/lib/python3.8/site-packages/numpy/lib/_datasource.py in open(path, mode, destpath, encoding, newline)
    193 
    194     ds = DataSource(destpath)
--> 195     return ds.open(path, mode, encoding=encoding, newline=newline)
    196 
    197 

~/.pyenv/versions/3.8.2/envs/profag/lib/python3.8/site-packages/numpy/lib/_datasource.py in open(self, path, mode, encoding, newline)
    533                                       encoding=encoding, newline=newline)
    534         else:
--> 535             raise IOError("%s not found." % path)
    536 
    537 

OSError: ../datasett/bevegelse.txt not found.

Grafikk

Oppgave 5

from turtle import *

forward(30)
right(90)
forward(40)
right(143.3)

Oppgave 6

from turtle import *

forward(500)
left(180-60)
forward(250)
left(180-90)
forward(433.013)

Oppgave 7

from turtle import *

forward(200)
left(180-90)
forward(200)
left(180-45)
forward(282.84)

Oppgave 8

from turtle import *

for j in range(2, 12):
    for i in range(180):
        forward(j)
        left(2)

Oppgave 9

from turtle import *

for i in range(180):
    forward(5)
    left(2)

Oppgave 10

from turtle import *

def trekant(AB, AC, a, b):
    forward(AB)
    left(180-a)
    forward(AC)
    left(b)
    goto(0, 0)

Oppgave 7

from turtle import *

leo = Turtle()
don = Turtle()

leo.penup()
leo.goto(100, 200)
leo.pendown()

don.penup()
don.goto(300, 300)
don.pendown()

leo.left(180-90)
leo.forward(100)
don.left(180)
don.forward(200)

Oppgave 8

from turtle import *

left(180-60)
forward(100)
left(180-60)
forward(100)
left(180)
forward(50)
right(60)
forward(50)

Oppgave 9

from turtle import *

for i in range(4):
    forward(100)
    left(90)

left(90)
forward(100)

right(30)
forward(100)
right(120)
forward(100)