🔒 Creating A Code

[raven panther]

@raven oyster

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[clear field]

you cant post files they get deleted you can upload them using

!paste

[raven panther]

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[raven oyster]

!paste

So, i know I start off my importing the libraries!

Let me do that real quick... is that fine so far or no?

[raven cobalt]

I know I cannot help with that math, but I believe you meant scipy.integrate instead of scipy integrate

[raven oyster]

is this better?

And I actually calculated the math... not code it.. lemme show you what i did

I need to figure out how to code it though

[grim thicket]

By "calculate the following quantities" (Q3), is it expecting exact values?

[raven oyster]

I assume so...

[raven cobalt]

Yes, looks correct, although I'm not sure of the exact structure/methods in scipy so cannot say for certain

[raven oyster]

i guess maybe we have all 256 values and we calculate this 256 times, since each number is different. ex. -12.8,-12.7,-12.6, etc.

and we need to calculate those quantities.. that is how i understand it

[grim thicket]

I guess so

[raven oyster]

it's a bit tough because if you look at my math, (if its correct), if i input value 1 into my equation, and then value 2 into my equation, the answers i receive are different... thats why i assume thats the case.

but rn I am trying to figure out how to input this into code.

[grim thicket]

This is one way to do it: ```py
for n in range(-128, 128):
x = n / 10
print(x)

[raven oyster]

shouldnt it be n/0.1?

[grim thicket]

n * 0.1 or n / 10

they both do the same thing

[raven oyster]

sorry give me a minute to figure out why

oh i see.

i just did another example like 40*0.1=4 and 40/10=4

makes sense

[grim thicket]

mhm

[raven oyster]

so here is how my code is looking so far

i took a shot on part of part a

as well part of part b

what do you think so far?

[grim thicket]

first, how familiar are you with matplotlib?

[raven oyster]

tbh not that familar... my professor expects that we know coding prior to taking the class but i have little to no knowledge in python.. i watched a video on a course of python

prior to asking these questiosn

[grim thicket]

that's alright

!e
The simplest x,y plot looks like this: ```py
import matplotlib.pyplot as plt

xs = [1, 2, 3, 4, 5]
ys = [0, 2, 5, 4, 3]

plt.plot(xs, ys)
plt.savefig("fig.png") # replace with plt.show() in your code

[raven panther]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

[raven oyster]

Oh, i see! i remember seeing stuff like that in my videos.. only thing is, before I create the plot... how do i insert the value that i received in print to my equation of sinx(ax)

and then ig another question is making it use all 256 values..

and then i think i can plot!

[grim thicket]

yup

are you familiar with using lists?

[raven oyster]

i found this when searching 'list' for python

is this what you're referring too?

[grim thicket]

Pretty much

we need to build 2 lists (x values and y values) to plot something

[raven oyster]

i see!

i assume the x axis is going to be f(x)=sinx(Ax) and y axis is going to be the 256 values.. or vise versa?

[grim thicket]

the x and y values will be interpreted as coordinates

[grim thicket]

so in this example the coordinates (1,0) (2,2) (3,5) (4,4) (5,3) were plotted

[raven oyster]

oh i see

but how do i know the coordinate numbers... dont i need to solve them first... and i cant yk, put a list of every 256 values?

i need to code it

like i understand the list. but how do i make a list without knowing the values

[grim thicket]

well, you know the x coordinate of each point, right?

[raven oyster]

-128,-127,-126,-125.... and so on

right?

[grim thicket]

divided by ten

-12.8, -12.7, etc.

[raven oyster]

yes

[grim thicket]

then you can use the formula for f(x) to calculate the y coordinate of each point

[raven oyster]

please let me know if thats acceptable

[grim thicket]

not quite

[raven oyster]

can i make a function for this so i can call it into my list or no?

[grim thicket]

you can start with an empty list and add items to it

[raven oyster]

what do you mean?

[grim thicket]

You can add items to a list like this: ```py
x_values = [] # empty list

x_values.append(1)
x_values.append(2)

print(x_values) # [1, 2]

[raven oyster]

append?

[grim thicket]

so if you did that in a loop, you could store all the x values from -12.8 to 12.7

[grim thicket]

yes?

[raven oyster]

oh kind of like a for loop like c++?

wait what is append

[grim thicket]

well, this is a for loop

[grim thicket]

some_list.append(thing) will add thing to the end of some_list

[raven oyster]

i guess where im kind of confused is ... lets say i make an empty list and then put append(1) and add onto it... do i have to manually do it from -12.7, all the way to 12.7 in one increment

[grim thicket]

you don't have to do it manually, that's what the for loop is for

[raven oyster]

but how do i call the loop into my append.. i need a function right, but how do i make my for loop a function (correct me if im using the wrong terminology)

[grim thicket]

you can call append inside the loop

[raven oyster]

can you provide an example.

[grim thicket]

!e ```py
lst = []
for num in range(5): # 0,1,2,3,4
lst.append(num)
print(lst)

[raven panther]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

[0, 1, 2, 3, 4]

[grim thicket]

see how lst starts out as empty but it gets populated by lst.append(num) inside the loop

[raven oyster]

oh i see! ty

why does it start empty. i always see it but i never understoof why

i see it in various codes but i never knew why

[grim thicket]

an empty list usually means stuff will be added later

[raven oyster]

oh okay!

[grim thicket]

like in this case, where we could list all the values from -12.8 to 12.7 inside the []

[raven oyster]

that makes a lot of sense

[grim thicket]

but instead we can add them all with a for loop

[raven oyster]

okay! So this is what i have so far 🙂

is it good so far 🙂

[grim thicket]

why not try run it?

[grim thicket]

yup

[raven oyster]

oh so something is wrong

[grim thicket]

for technical reasons, range can't accept decimal numbers

you have to use something similar to the for loop in lines 7-9

[raven oyster]

?

lol nope

didnt work

[grim thicket]

remember, num / 10 is the singular x value

not the entire list of x values

[grim thicket]

looks good

[raven oyster]

that worked!

yay

now y axis

[grim thicket]

yup

so given an x value, can you calculate f(x) ?

[raven oyster]

so ig i have to input the equation but how do i imput the value i received from the equation in the image into my new equation

Well yes.

if i input what i received for "a", i can receive a equation where if i input an x value, ill be able to calculate for F(X)

[grim thicket]

yup

[raven oyster]

how do i assign the function a to my equation a%b+1

[grim thicket]

I think defining a and b as 3 and 4 is a bit misleading here

[raven oyster]

yeah lol

wgat do you recommend i change it too?

what

[grim thicket]

I would simply define a = 4%3 + 1

so it's the same as in the question

[raven oyster]

okay!

ty!

lol im suprised i didnt think of that

i just made it harder for no reason

rn im trying to input the sinc equation

give me a minute

i tried this but sinc isnt found in the library... can i do math.sin(apix_axis)/apix_axis

its bc a = 2 so the equation would be sin(2pix)/2pix

[grim thicket]

math.sin does exist, but it will only take single x values

[raven oyster]

oh not math.sin

math.sinc

this is what i did... please let me know if im right so far... i think it should be correct.

[grim thicket]

you're getting closer

[raven oyster]

Can i please get a hint?

[grim thicket]

so now you can calculate f(x) for a given x value

now to do it for each x value in your range

[raven oyster]

??

[grim thicket]

not quite... x_axis is a list of all the x values

but you need to calculate this for each x value

[raven oyster]

lol i feel like im making it worse

am i getting any closer lOL

[grim thicket]

you can use the same loop for both x and y

i.e.: ```py
x_axis = []
y_axis = []
for ...:
# calculate x value
x_axis.append(...)
# calculate y value
y_axis.append(...)

[raven oyster]

lol wait

im confuse

give me a few minutes

?

lol that didnt work

am i getting closer or no?

[grim thicket]

the calculation for the y coordinate has to happen inside the loop

because it will only work on single x values, not a list of them

[raven oyster]

?

[grim thicket]

closer

[grim thicket]

instead of making random changes, think logically about what the program will do

hint: what is line 19 doing?

[raven oyster]

well here is how i am approaching it... we have a for loop so that is going from -128 to 128 ... and we are stating in line 18 and 19 that we are dividing those number by 10 and adding a number to that list... and then i insert the equation

[grim thicket]

okay

and what y_axis meant to store?

[raven oyster]

its meant to store the equation.

but go through the range of (-128,128)

[grim thicket]

not really

it stores the y coordinates of each point in a list

[raven oyster]

how about something like this .. bc im making a list with my equation?

[raven oyster]

would you be able to help me work on this tomorrow? are you busy?

[grim thicket]

closer; you just need to change x_axis in the formula

[raven oyster]

to num/10?

[grim thicket]

yup, since that's the current x value

[raven oyster]

wow! im getting it lol

[grim thicket]

you could also assign it to a variable like so: ```py
for num in range(-128, 128):
x = num / 10
x_axis.append(x)
y_axis.append( ... ) # use 'x' instead of 'num/10'

[raven oyster]

my professor added coding tips, do you know what labels is... is it laveling the x axis and y axis title or the title or the grapg... im a bit confused

and Oh okay!

wait odd im getting an error

[grim thicket]

oh, right

hmm, I guess we have to special case that?

[raven oyster]

wdym?

[grim thicket]

sinc(0) = 1, right?

that has to be handled separately because the denominator will be 0

[raven oyster]

oh i see

you're right

if then statement... like if 0 , dont do anything, if not, then use the equation

?

[grim thicket]

I think it's worth defining a new function here

[grim thicket]

but yeah thats the gist of it

[raven oyster]

could you provide me an example on how you would do it in python.. ive done it in c++ but that was A WHILE AGO. I DONT REALLY RECALL IT AS MUCH

also are you busy tomorrow?

[grim thicket]

example of a function or if statement?

[raven oyster]

if

[grim thicket]

if condition:
    ...
else:
    ...

[raven oyster]

like i dont know how to say if not 0 ,

i know if 0 is if = 0

[grim thicket]

I have school tomorrow so I guess so

[raven oyster]

ios not ==

[grim thicket]

Are you looking for !=?

[raven oyster]

no like how do i say if not 0, is it if == 0, 'do not not use equation' and if =0 , 'isnsert equation'

[grim thicket]

If-else?

[raven oyster]

i see.. ill just search that up. what function should i make since you recommended it

[grim thicket]

sinc(x)

[raven oyster]

:0 uh i would recommend creating a new help page...

[old hemlock]

Ohhhh mb

Wrong side

[raven oyster]

i completed up to part c ... if you can help me with part d and e, that would be great 🙂

[raven panther]

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