我正在阅读John Zelle的Python编程,并且只限于下图所示的一种练习。
您可以在下面查看我的代码。我知道代码很丑陋。 (任何提示都表示赞赏)
到目前为止,这是我的代码:
from graphics import *
def regression():
# creating the window for the regression line
win = GraphWin("Regression Line - Start Clicking!", 500, 500)
win.setCoords(0.0, 0.0, 10.0, 10.0)
rect = Rectangle(Point(0.5, 0.1), Point(2.5, 2.1))
rect.setFill("red")
rect.draw(win)
Text(rect.getCenter(), "Done").draw(win)
message = Text(Point(5, 0.5), "Click in this screen")
message.draw(win)
points = [] # list of points
n = 0 # count variable
sumX = 0
sumY = 0
while True:
p = win.getMouse()
p.draw(win)
# if user clicks in a red square it exits the loop and calculates the regression line
if (p.getX() >= 0.5 and p.getX() <= 2.5) and (p.getY() >= 0.1 and p.getY() <= 2.1):
break
n += 1 # count of the points
# get the sum of the X and Y points
sumX = sumX + p.getX()
sumY = sumY + p.getY()
# tuple of the X and Y points
dot = (p.getX(), p.getY())
points.append(dot)
avgX = sumX / n
avgY = sumY / n
top = 0
bottom = 0
# my ugly attempt at the regression equation shown in the book
for i in points:
gp = 0
numer = points[gp][0] * points[gp][1]
top = top + numer
denom = points[gp][0] ** 2
bottom = bottom + denom
gp += 1
m = (top - sumX * sumY) / (bottom - sumX ** 2)
y1 = avgY + m * (0.0 - avgX)
y2 = avgY + m * (10.0 - avgX)
regressionline = Line(Point(0, y1), Point(10.0, y2))
regressionline.draw(win)
raw_input("Press <Enter> to quit.")
win.close()
regression()
当我运行程序时,回归线似乎永远不是最合适的。我相信我在代码中错误地解释了回归方程。需要更改什么才能获得正确的回归线?
最佳答案
问题:
from my_library import *
应该避免;最好准确地指定您要从中获得什么。这有助于使您的命名空间保持整洁。 这是我的代码的重构版本:
from graphics import GraphWin, Point, Line, Rectangle, Text
def draw_window()
# create canvas
win = GraphWin("Regression Line - Start Clicking!", 500, 500)
win.setCoords(0., 0., 10., 10.)
# exit button
rect = Rectangle(Point(0.5, 0.1), Point(2.5, 2.1))
rect.setFill("red")
rect.draw(win)
Text(rect.getCenter(), "Done").draw(win)
# instructions
Text(Point(5., 0.5), "Click in this screen").draw(win)
return win
def get_points(win):
points = []
while True:
p = win.getMouse()
p.draw(win)
# clicked the exit button?
px, py = p.getX(), p.getY()
if 0.5 <= px <= 2.5 and 0.1 <= py <= 2.1:
break
else:
points.append((px,py))
return points
def do_regression(points):
num = len(points)
x_sum, y_sum, xx_sum, xy_sum = 0., 0., 0., 0.
for x,y in points:
x_sum += x
y_sum += y
xx_sum += x*x
xy_sum += x*y
x_mean, y_mean = x_sum/num, y_sum/num
m = (xy_sum - num*x_mean*y_mean) / (xx_sum - num*x_mean*x_mean)
def lineFn(xval):
return y_mean + m*(xval - x_mean)
return lineFn
def main():
# set up
win = draw_window()
points = get_points(win)
# show regression line
lineFn = do_regression(points)
Line(
Point(0., lineFn(0. )),
Point(10., lineFn(10.))
).draw(win)
# wait to close
Text(Point(5., 5.), "Click to exit").draw(win)
win.getMouse()
win.close()
if __name__=="__main__":
main()
关于python - Python初学者-如何使点击次数等于回归线并以图形方式显示?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/10610391/