热流的数值模拟

Question

我是编码世界的新手，所以在这里放轻松吧。我正在尝试创建一个方形平底锅的数字模拟，正好在一个点加热，即用电线加热。不幸的是，我的功能一直在使我的doc.tests失败，我不明白为什么。任何帮助将不胜感激

import sys
sys.path.append('/home/courses/python')
from logic import *
from numpy import *



def create_plate(size, plate_temperature):
    plate_temperatures = empty([size, size])
    plate_temperatures[:,:] = plate_temperature
    return plate_temperatures

def simulate_plate(plate_temperatures,hot_x,hot_y, hot_temp,air_temp, htc,hcc,ahtc):
    """ Simulate one time step on the plate, given array of temperatures, etc. """
    precondition()

    plate_temperatures[hot_x,hot_y] = hot_temp 

    #number rows = len(input)     
    #number cols = len(input[0]) 

    # First, calculate heat flow _into_ every 1cmx1cm square
    heat_in = zeros_like(plate_temperatures)
    # The "length" of an array is the number of rows; the length of a row is the number of columns.
    #because the plate is always a square precondition range(len(plate_temperatures)) ==range(len(plate_temperatures[row_place]))

    for row_place in  range(len(plate_temperatures)): # is this accurate?
        for column_place in range(len(plate_temperatures[row_place])):

            plate_temperatures[hot_x,hot_y] = hot_temp

            faces = 2   # Number of faces exposed to the air, top and bottom of plate
            if(column_place!=0): #square is not on left edge of plate
                from_left = (plate_temperatures[row_place,column_place-1] - plate_temperatures[row_place,column_place]) * htc # heat from left     

            else:#square is on left edge; nothing to the left of it
                 from_left = 0

            if(column_place<(len(plate_temperatures[row_place])-1)): #square is not on the right edge of plate
                from_right = (plate_temperatures[row_place,column_place+1] - plate_temperatures[row_place,column_place]) * htc # heat from right

            else: #square is on the right edge; nothing to the right of it
                from_right = 0

            if row_place !=0: #square is not on the top edge of plate 
                from_above =(plate_temperatures[row_place+1,column_place] - plate_temperatures[row_place,column_place]) * htc # heat from above
            else: # square is on the top edge of plate
                from_above = 0

            if row_place< (len(plate_temperatures)-1):#square is not on the bottom edge of the plate
                from_below = (plate_temperatures[row_place-1,column_place] - plate_temperatures[row_place,column_place]) * htc # heat from below   

            else:#square is on the bottom edge of the plate
                from_below = 0

            from_air = (air_temp - plate_temperatures[row_place,column_place]) * faces * ahtc # heat from air

            heat_in[row_place,column_place] = from_left + from_right + from_above + from_below + from_air

            # Now, add the heat we found above to the old temperatures
        plate_temperatures[row_place, column_place]  += (heat_in[row_place,column_place] * hcc)

    # restore the temperature of the heated spot
        plate_temperatures[hot_x,hot_y] = hot_temp



def simulate_plate_N_steps(plate_temperatures,hot_x,hot_y, hot_temp,air_temp, htc,hcc,ahtc, N):
    """ Just call the one-time-step function N times... """
    all_averages = []  # log of temperatures at end of time steps
    for t in range(N):
        simulate_plate(plate_temperatures,hot_x,hot_y, hot_temp,air_temp, htc,hcc,ahtc)
        all_averages.append(average_temp(plate_temperatures))
    print "Completed", N, "simulated time steps; end-step average temps were:", all_averages


# copied from  http://docs.python.org/lib/module-doctest.html
def _test():
    import doctest
    result = doctest.testmod()
    if result[0] == 0:
        print "Wahoo! Passed all", result[1], __file__.split('/')[-1], "tests!"
    else:
        print "Rats!"

if __name__ == "__main__": _test()