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How can I loop over random numbers to get coordinates for my class?

I need a loop over all of my clans, which are instances of a class. Each clan needs to be assigned a position, a x and a y coordinate. Preferably as two lists or as a single tuple (but no idea how I specify that). This is how it works for the 1st clan. Afterwards I always have to check, if the position is already assigned. If so, you have to search for a new position until it is free.
I then coded my class like this:
width = 20
height = 20
no_of_clans = 50
import random
class clan:
def __init__(self, index, position_list):
self.index = index
self.position_list = position_list
def index(no_of_clans):
return list(range(1, no_of_clans +1))
def position_list(self):
for i in range(1, no_of_clans +1):
positions = ()
if i ==1: #i can do it either like this
positions = [(random.randint(0, width)), (random.randint(0, height))]
positions.append(x,y)
else: #or like this, I do not know, which one is better, both are running
x = (random.randint(0, width))
y = (random.randint(0, height))
#check if x and y not already used
#assert
positions.append(x,y)
return positions
print(positions)
how can I assign positions randomly when also using 0.5 steps? I always get an error message.
I never get a list of my positions back, but I do not know what I did wrong.
I know those are probably fairly basic questions but I am quite new to python an already searched for 5h today and I really do ot know where to start anymore. I would be really happy if someon could help me. Thank you so much in advance <3

I found the answer to my original question in this post:
Coordinates of the edges of a honeycomb grid in python
Will update if I am finished with the class-thing :)

How to efficiently code for updating many variables in a script using Tkinter?

I am designing a Tkinter interface to be compatible with my datalogging script. Both are still WIP, but close to getting merged. This script is used for a Raspberry Pi to periodically make measurements using different sensors. In this case, of plants.
I have various Entry widgets to access my variables (input channels, measure interval and measurements per average value ), so i can change them without reprogramming the script itself.
3 entry widgets are associated with the textvariables:
gpio_light1_entry, interval_light1_entry, amount_light1_entry
The actual variables used by the datalogging script are:
gpio_light1, interval_light1, amount_light1
I want to define a function (That i will bind to a button.). That retrieves the entry window value (gpio_light1_entry.get()) and that updates the script variable.
Now I could just use:
gpio_light1 = gpio_light1_entry.get()
However I have at least 12 variables per plant. So coding it like this for some 12 times seems very inefficient to me.
I was thinking of using a for loop and lists.
settings_gpio1 = [gpio_light1, gpio_temp1, etc]
settings_gpio1_entry = [gpio_light1_entry, gpio_temp1_entry, etc]
But this had some problems:
1- It seems that changing a value in a list, does not change the variable used to construct the list.
2- I do not know how to make a "double" for loop to use both the _entry and non entry lists.
3- The _entry list needs a .get() function to retrieve the values, this function does not work on lists directly, but can be solved with a for loop.
Does anyone know a more efficient or easier way to reach my goal?

I advise you to create a class for each Gpio access:
The class it self should hold the values for accessing the hardware and displaying it.
If, for some reason, you already have the list of available gpios and entries, you can do some thing like this:
class Gpio:
def __init__(self,setting, entry):
self.setting = setting
self.entry = entry
def Get(self):
#Do whatever you need with self.entry
return 0
def __str__(self):
return self.setting
#staticmethod
def FromArray(names,settings, entries):
assert(len(settings) == len(entries) == len(names))
ret = {}
for i in range(len(settings)):
ret[names[i]] = Gpio(settings[i], entries[i])
return ret
Here I put a random example, I don't know what values you are going to use:
gpio_light1 = 33
gpio_light_entry = "hardware_address"
gpio_temp_entry = "0x80001234"
names = ["gpio_light1", "gpio_temp1"]
settings_gpio = [gpio_light1, "gpio_temp1"]
settings_gpio_entry = [gpio_light_entry, gpio_temp_entry]
access = Gpio.FromArray(names, settings_gpio, settings_gpio_entry)
print access["gpio_light1"].Get()

How to display an Image with python, without pyglet or similar?

So, what I am trying to do in detail:
I have a device that acts as a display, although is technically not one (that's not really important, it can be handled like a normal display) and I want to display a series of images on it. When each image is displayed i call a function that takes readings from another device. So far I have used pyglet for that and I can get it to display the images in the correct order and where I want them, but the readings taken seem not to correspond to the right image.
The simplest way to explain what I want to do is:
for a in range(10):
display('image%d'%a)
values(a) = measure()
Imagine values being initiated in the correct form.
What I tried so far was:
import pyglet
import numpy as np
size = 64
no = 512/size
a,b,c = (0,0,0)
values = np.zeros((no,no,3))
display = pyglet.window.get_platform().get_default_display()
screens = []
for screen in display.get_screens():
screens.append(screen)
window = pyglet.window.Window(screen = screens[1], fullscreen=1)
#here i choose the mentioned device, since it is connected to my computer via display port
#window.event
def update(dt):
global a,b,c
if a == no/2. and b == no/2.:
values[a,b,c] = 0
window.clear()
else:
image = pyglet.image.load('folder_%d/grating_%d_%d_%d.bmp' % (size,a,b,c))
window.clear()
print (a,b,c)
image.blit(0,0)
values[a,b,c] = measure()
c+=1
if c == 3:
b += 1
c = 0
if b == no:
a += 1
b = 0
if a == no:
pyglet.app.exit()
pyglet.clock.schedule_interval(update, .2)
pyglet.app.run()
where measure() is my own function. "no" is an index for my images, they range from (0,0,0),(0,0,1),(0,0,2),(0,1,0)... to (no,no,2) and are called to be called one by one. Also the case of a = b = no/2 is a special case that is of no special importance to my problem, I think.
first of all: I am pretty sure this is neither elegant nor efficient but I am not creating software that anyone else is ever likely to use. I am also aware that using global variables is bad practice but their use is due to me not knowing how to use eventloops correctly.
I am not happy with this solution, because the readings i take always seem to correspond to the previous image.
I guess I misuse the eventloop badly, but the pyglet documentation does not really help me here.
Also I feel like I am building a whole truck just to carry a bag across the street...
I have already looked into pyplot as an alternative, since the imshow() function works in the way I want, but the plotting libraries seem to display images in random sizes, which I cannot figure out how to control properly.
I appreciate any help on using pyglet correctly as well as alternative libraries that can help.
Thank you already,
Mopsi

An extra-long comment, that requires formatted code
From your example, you don't need a,b,c outside of the update function and all the global stuff is about having values that stay alive across invocations. If I'm correct this is better suited by a closure, like
...
def make_update(no, window):
from itertools import product
abcs = product(range(no),range(no),range(3))
#window.event
def _update(...):
try:
a, b, c = next(abcs)
except StopIteration:
... wind up ...
...
return _update
update = make_update(no, window)
...

Alright, I did not actually solve the problem but found a workaround:
I just flatten my image nomenclature, e.g
0_0_0 -> 000
0_0_1 -> 001
0_0_2 -> 002
0_1_0 -> 003
etc.
With values now being an array with dimensions [no*no*3,1]
And since for the n-th iteration and therefore n-th measurement I see the (n-1)th image, I simply add a dummy image and assign the n-th measured value to values[n-1].
The first measurement being useless is no problem here, since values[-1] is the last element, which gets overwritten with a meaningful measurement in the end.
Since the number of images is known and predetermined I can reshape my array of values afterwards.
If anyone cares to explain why no the displayed image is shifted by one iteration (with no image at all being displayed at the first iteration) please go ahead.

How to initialize data for a function that is repeatedly called

This is surely a beginner's question, I'm just having trouble searching for it.
What I want to do is calculate points on a circle for thousands of circles which I will later render. Because I will be rendering many thousands of circles a second, I thought I'd try to avoid unncessary overhead. To do this, I've created a function that calculates a number of points (which I want to be variable, a larger circle will need more points calculated) on a unit circle, and another function which can take these points, translate them and then scale by the radius.
My original code ended up something like this:
class Circle():
...
def CalcCircle(segments):
does some stuff to calculate generic coordinates
def CreateCircle(x, y, r, segments):
does some stuff to create a circle using CalcCircle(segments)
Obviously the problem was that even though I might only want to create circles with 20 segments, I was calling the CalcCircle function (and repeating the same calculations) every time I called CreateCircle.
The only way I could figure out how to fix this was:
class Circle():
...
def CalcCircle(segments):
does some stuff to calculate generic coordinates
CreateCircle_has_not_been_run = True
def CreateCircle(x, y, r, segments):
if Circle.TransCircle_has_not_been_run:
generic_circle = Circle.CalcCircle(segments)
Circle.CreateCircle_has_not_been_run = False
does some stuff to create a circle using generic_circle
I've never formally learnt programming so I'm not sure if this is considered good design. Surely it would become messy if every time I wanted to "initialize" data or call a function only on the first run through I had to make a random class variable. The reason I ask is I'm constantly running into this problem, so I assume there must be a standard way of doing it.
Edit: An example of how the call will be made.
#window.event
def on_draw():
window.clear()
width = window.get_size()[0]
height = window.get_size()[1]
radius = int(width/50)
segments = int(radius*1.5)
for i in range(N):
pyglet.gl.glColor3f(0.05,0.2,0.9)
DrawCircle(positions[i][0],positions[i][1],width,segments)
DrawCage(width,height)
DrawLabel(width,height)
etc.
I'm aware that there's problems here but I'm just trying to illustrate the example (positions comes from the update function if anyone is wondering). As I've said earlier, this is a problem I run into all the time.
I could call Circle.CalcCircle() from the on_resize() function as per Achim's suggestion. I have a hard time believing however that standard practice is to stick two random functions into a class (as it stands neither of them necessarily need to even be in the Circle class), one of which is implicitly dependent on the other and both of which are called in different parts of the code.

I would do something like this:
class Circle:
def __init__(self):
self.unit_circle_points = None
def CalcCircle(self, segments):
# Do some stuff to calculate segments,
# assign calculated values to class attribute
self.unit_circle_points = calculated_points
def CreateCircle(self, X, y, r, segments):
# If circle points have not yet been calculated then calculate
# and store, else just load stored points
if self.unit_circle_points is None:
self.CalcCircle(segments)
unit_circle_points = self.unit_circle_points
# Now use unit_circle_points to do some calculations
Every time you instantiate a circle object it will come with an attribute named unit_circle_points that is initialized to None. When you call the CreateCircle method on that object for the first time it will see that the unit_circle_points attribute is None and perform the necessary computations by calling CalcCircle, storing the results. On subsequent calls to the CreateCircle method of this Circle object the unit_circle_points attribute will no longer be None, and the method will simply use the values stored in the attribute.
Edit:
If this requires to much "implicit" behavior for your taste, you can shift things around so that CalcCircle must be called explicitly by the user to generate the pre-calculated data.
class Circle:
def __init__(self):
self.unit_circle_points = None
def CalcCircle(self, segments):
# Do some stuff to calculate segments,
# assign calculated values to class attribute
self.unit_circle_points = calculated_points
return self
def CreateCircle(self, X, y, r):
# If circle points have not yet been calculated then raise an error,
# else load previously calculated points
if self.unit_circle_points is None:
raise Exception("You'd better explicitly call CalcCircle first.")
unit_circle_points = self.unit_circle_points
# Now use unit_circle_points to do some calculations

What is the most effective way to incremente a large number of values in Python?

Okay, sorry if my problem seems a bit rough. I'll try to explain it in a figurative way, I hope this is satisfactory.
10 children. 5 boxes. Each child chooses three boxes. Each box is opened:
- If it contains something, all children selected this box gets 1 point
- Otherwise, nobody gets a point.
My question is about what I put in bold. Because in my code, there are lots of kids and lots of boxes.
Currently, I proceed as follows:
children = {"child_1" : 0, ... , "child_10": 0}
gp1 = ["child_3", "child_7", "child_10"] #children who selected the box 1
...
gp5 = ["child_2", "child_5", "child_8", "child_10"]
boxes = [(0,gp1), (0,gp2), (1,gp3), (1,gp4), (0,gp5)]
for box in boxes:
if box[0] == 1: #something inside
for child in box[1]:
children[child] += 1
I worry mainly about the for loop that assigns each child an extra point. Because in my final code, I have many many children, I fear that doing so would slow the program too.
Is there a more efficient way for all children of the same group may have their point faster?

Represent children as indices into arrays, not as strings:
childrenScores = [0] * 10
gp1 = [2,6,9] # children who selected box 1
...
gp5 = [1,4,7,9]
boxes = [(0,gp1), (0,gp2), (1,gp3), (1,gp4), (0,gp5)]
Then, you can store childrenScores as a NumPy array and use advanced indexing:
childrenScores = np.zeros(10, dtype=int)
...
for box in boxes:
if box[0]:
childrenScores[box[1]] += 1 # NumPy advanced indexing
This still involves a loop somewhere, but the loop is deep inside NumPy instead, which should provide a meaningful speedup.

The only speed up that I can think of is to use numpy arrays and stream the sum operation.
children[child] += np.ones(len(children[child]))
You should benchmark the operation and see if that is too slow for your business case.

What I would do
In the gpX lists don't save the "name of the child" (e.g. "child_10") but save a reference to the child's number of points.
How to do that
Using the fact that lists are objects in python, you can:
Change the children dict to look like: children = {"child_0": [0], "child_1": [0], ...} and so on.
When you assign to group, don't assign the key but assign the value (e.g. gp1.append(children["child_0"])).
The loop should then look like: for child in box[1]: child[0]+=1. This WILL update the children dict.
EDIT:
Why this is faster:
Because you leave out the part where you search for children[child], which might be costly.
This technique works because by storing the totals in a mutable type, and appending those values to the group lists, both the dict value and each box's list value will point to the same list entries, and changing one will change the other.

Two general points:
(1) Based on what you've told us, there's no reason to focus your energy on minor performance optimizations. Your time would be better spent thinking about ways to make your data structures less awkward and more communicative. A bunch of interrelated dicts, lists, and tuples quickly becomes difficult to maintain. For an alternative, see the example below.
(2) As the game designer, you understand that events follow a certain sequence: first the kids select their boxes, and later they discover whether they get points for them. But you don't have to implement it that way. A kid can choose a box and get points (or not) immediately. If there's a need to preserve the child's ignorance about such outcomes, the parts of your algorithm that depend on such ignorance can enforce that veil of secrecy as needed. The upshot: there is no need for a box to loop through its children, awarding points to each one; instead, award the points immediately to kids as boxes are selected.
import random
class Box(object):
def __init__(self, name):
self.name = name
self.prize = random.randint(0,1)
class Child(object):
def __init__(self, name):
self.name = name
self.boxes = []
self.score = 0
self._score = 0
def choose(self, n, boxes):
bs = random.sample(boxes, n)
for b in bs:
self.boxes.append(b)
self._score += b.prize
def reveal_score(self):
self.score = self._score
boxes = [Box(i) for i in range(5)]
kids = [Child(i) for i in range(10)]
for k in kids:
k.choose(3, boxes)
# Later in the game ...
for k in kids:
k.reveal_score()
print (k.name, k.score), '=>', [(b.name, b.prize) for b in k.boxes]

One way or another, you're going to be looping over the children, and your answer appears to avoid looping over children who don't get any points.
It might be slightly faster to use filter or itertools.ifilter to pick the boxes that have something in them:
import itertools
...
for box in itertools.ifilter(lambda x: x[0], boxes):
for child in box[1]
children[child] += 1

If you don't need to immediately print the number of points for every child, you could calculate it on demand, thus saving time. This could help if you only need to query a child every now and then for how many points it has. You can cache each result as you obtain is so you don't go about calculating it again the next time you need it.
Firstly, you'll need to know which groups a child belongs to. We'll store this information as map we'll call childToGroupsMap, which will map each child to an array holding the boxes it belongs to, like so:
childToGroupsMap = {}
for child in children:
childToGroupsMap[child[0]] = []
for box in boxes:
for child in box[1]:
if (box[1] not in childToGroupsMap[child]):
childToGroupsMap[child].append(box[1])
This constructs the reverse map from children to boxes.
It'll also help to have a map from each box to a boolean representing whether it's been opened:
boxToOpenedMap = {}
for box in boxes:
boxToOpenedMap[box[1]] = box[0]
Now, when someone queries how many points a child has, you can go through each of the boxes it belongs to (using childToGroupsMap, of course), and simply count how many of those boxes have been mapped to 1 in the map boxes:
def countBoxesForChild(child):
points = 0
for box in childToGroupsMap[child]
if boxToOpenedMap[box] == 1:
points += 1
return points
To make this better, you can cache the resulting number of points. Make a map like so:
childToPointsCalculated = {}
for child in children:
childToPointsCalculated[child[0]] = -1
Where the -1 denotes that we don't yet know how many points this child has.
Finally, you can modify your countBoxesForChild function to exploit the cache:
def countBoxesForChild(child):
if childToPointsCalculated[child] != -1
return childToPointsCalculated[child]
points = 0
for box in childToGroupsMap[child]
if boxToOpenedMap[box] == 1:
points += 1
childToPointsCalculated[child] = points
return points