Create a random walk data class, why don't you create an instance to arguments?-CodePudding

Recently in learning Python from entry to practice the book, when doing data visualization cases encountered a little problem, is to survive a random walk data classes, and then create an instance, don't know why below rw=RandomWalk () can need not give argument here? Please god help me, thank you!

# 15.3.1 create RandomWalk ()

From the random import choice

The class RandomWalk () :
"" "a generated random walk data class ", "

Def __init__ (self, num_points=5000) :
"" "initialization properties of random walk "" "
Self. Num_points=num_points
Self. X_values=[0] # all random walks in (0, 0)
Self. Y_values=[0]

Def fill_walk (self) :
"" "computing random walk contains all points "" "
# walk continuously, until the list reaches the specified length
While len (self x_values) & lt; Self. Num_points:
# decides the direction and distance along this direction
X_direction=choice ([1, 1])
,1,2,3,4 x_distance=choice ([0])
X_step=x_direction * x_distance

Y_direction=choice ([1, 1])
,1,2,3,4 y_distance=choice ([0])
Y_step=y_direction * y_distance

# refused to mark time
If x_step==0 and y_step==0:
The continue

# computing the next point of x and y values
Next_x=self. X_values [1] + x_step
Next_y=self. Y_values [1] + y_step

Self. X_values. Append (next_x)
Self. Y_values. Append (next_y)

# to create a RandomWalk instance, and include them points are mapped
Rw=RandomWalk () # why RandomWalk instance without argument?
Rw. Fill_walk ()
PLT. Scatter (rw) x_values, rw. Y_values, s=15)
PLT. The show ()

CodePudding user response:

Because RandomWalk init num_points assignment for 5000 already inside, don't need to preach to participate, you can modify the code to pass arguments at the following:

 
From the random import choice 
The import matplotlib. Pyplot as PLT 


The class RandomWalk () : 
"" "a generated random walk data class ", "
Def __init__ (self, num_points) : 
"" "initialization properties of random walk "" "
Self. Num_points=num_points 
Self. X_values=[0] # all random walks in (0, 0) 
Self. Y_values=[0] 

Def fill_walk (self) : 
"" "computing random walk contains all points "" "
# walk continuously, until the list reaches the specified length 
While len (self x_values) & lt; Self. Num_points: 
# decides the direction and distance along this direction 
X_direction=choice ([1, 1]) 
,1,2,3,4 x_distance=choice ([0]) 
X_step=x_direction * x_distance 

Y_direction=choice ([1, 1]) 
,1,2,3,4 y_distance=choice ([0]) 
Y_step=y_direction * y_distance 

# refused to mark time 
If x_step==0 and y_step==0: 
The continue 

# computing the next point of x and y values 
Next_x=self. X_values [1] + x_step 
Next_y=self. Y_values [1] + y_step 

Self. X_values. Append (next_x) 
Self. Y_values. Append (next_y) 


# to create a RandomWalk instance, and include them points are mapped 
Rw=RandomWalk (# 5000) to send and assignment to num_points 
Rw. Fill_walk () 
PLT. Scatter (rw) x_values, rw. Y_values, s=15) 
PLT. The show ()