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我寫了一個python腳本,它根據速度和角度顯示拋射體的覆蓋距離。功能無法識別全局變量
但是,它不會讀取用戶返回的另一個函數(ask_values())的那兩個變量。
什麼阻止了cover_distance()函數讀取用戶在ask_values()中輸入的2個變量(θ和速度)?
這裏是程序的輸出:
Projectile angle: 10
Velocity: 10
Angle: 10.0 Speed: 10.0
Angle: 0.0 Speed: 0.0
Distance covered: 0.0
這裏是程序本身:
# IMPORT MODULES
from math import * # Import all methods/attributes from math module
import sys # Import sys.exit()
# DECLARE VARIABLES
theta = 0.0 # theta = angle at which the projectile is launched
velocity = 0.0 # velocity = speed of the projectile
percent_distance_var = 0.0 # percent_distance_var = percentage of the covered distance
max_distance_var = 0.0 # max_distance_var = maximum distance
covered_distance_var = 0.0 # covered_distance_var = covered distance
# Covered distance
def covered_distance(theta_, velocity_, covered_distance_var_): # Arguments: (theta, speed, covered_distance_var)
covered_distance_var_ = 0.2041*((velocity_)**2)*sin(theta_)*cos(theta_) # Calculate 0.2041*((velocity)**2)*sin(theta)*cos(theta)
data = dict(angle=theta_, speed=velocity_, distance=covered_distance_var_)
print("Angle: {angle} Speed: {speed} \n \nDistance covered_: {distance}".format(**data)) # Doesn't print out the correct variables
return covered_distance_var_ # Return covered_distance_var
# Ask user for values
def ask_values(theta, velocity):
theta = float(input("Projectile angle: \t"))
velocity = float(input("Velocity: \t \t"))
print("Angle: {} Speed: {}".format(theta, velocity)) # Prints out the correct variables
return(theta, velocity)
def main():# Main method
ask_values(theta, velocity) # Ask for values
covered_distance(theta, velocity, covered_distance_var)
# EXECUTE CODE
if __name__ == "__main__": # If "__main__" statement
main() # Main() method
你可以用'全球some_global_variabe'訪問功能全局變量 –
@NipunGarg我會強烈建議不要使用'全球'在你的所有功能。上面的函數本質上是好的,輸出只需要分配給正確的名稱。 –
@ juanpa.arrivillaga在這種情況下,使用全局變量在這裏完全沒用。 –