新手Python：如何与嵌套循环交互图层

Question

I've dealing with the code below with such a long time. I have to show in a raster image the result of calculating the cost of the electricity for a solar plant. The thing is that I have to interact a layer "DNI" (direct normal irradiation) with the formula, and the value of the formula changes with a factor for each year (costReductionFactorPlant) during the 30 years of the life plant. The factors are shown below.

When I run the code, I receive the following error:

Runtime error 
Traceback (most recent call last):
  File "<string>", line 56, in <module>
  File "c:\program files (x86)\arcgis\desktop10.1\arcpy\arcpy\sa\Functions.py", line 4049, in Times
    in_raster_or_constant2)
  File "c:\program files (x86)\arcgis\desktop10.1\arcpy\arcpy\sa\Utils.py", line 47, in swapper
    result = wrapper(*args, **kwargs)
  File "c:\program files (x86)\arcgis\desktop10.1\arcpy\arcpy\sa\Functions.py", line 4046, in wrapper
    return _wrapLocalFunctionRaster(u"Times_sa", ["Times", in_raster_or_constant1, in_raster_or_constant2])
RuntimeError: ERROR 000732: Input Raster: Dataset D:_ArcGIS\Python\LCOE_test does not exist or is not supported
>>> 

I'm afraid that there is something wrong when calling the layer "DNI". But no clue. Maybe there is also an error with the loop... I've tryed to look at it also, for me looks good, but I'm not an expert.

I'm running ArcGis 10.1. All suggestions are more than welcome.

CODE:

import arcpy, os, sys
from arcpy import env
from arcpy.sa import *

# Set Workspace
env.workspace = "D:\02_ArcGIS\Python\LCOE_test"

# Check out the ArcGIS Spatial Analyst extension license
arcpy.CheckOutExtension("Spatial")

# Variables definition
capacity = 100000
actualOutput = .94 * capacity
storageHours = 16
loadFactor = (.57 * storageHours + 7.1)/24
costReductionFactorPlant = [0.4790, 0.4533, 0.4297, 0.4080, 0.3880, 0.3696, 0.3526, 0.3368, 0.3222, 0.3087, 0.2961, 0.2844, 0.2735, 0.2633, 0.2538, 0.2449, 0.2366, 0.2288, 0.2215, 0.2146, 0.2081, 0.2021, 0.1964, 0.1910, 0.1859, 0.1811, 0.1765, 0.1723, 0.1682, 0.1643, 0.1607]
efficiency = [0.1822, 0.1827, 0.1831, 0.1834, 0.1837, 0.1840, 0.1841, 0.1843, 0.1844, 0.1845, 0.1846, 0.1847, 0.1847, 0.1848, 0.1848, 0.1849, 0.1849, 0.1849, 0.1849, 0.1849, 0.1849, 0.1850, 0.1850, 0.1850, 0.1850, 0.1850, 0.1850, 0.1850, 0.1850, 0.1850, 0.1850]
years = 30
i = .1
ir = .01
lcoePlantTotal = 0
productionPlant = loadFactor * actualOutput * 8760
DNI =  "D:\02_ArcGIS\Python\LCOE_test" #layer#

Count=len(costReductionFactorPlant)+ 1
counter=1

while counter < Count:
    for i in range(counter,(counter+1)):

            # Set the cell size environment using a keyword.
            arcpy.env.cellSize = "MAXOF"

            # Set the extent environment using a keyword
            arcpy.env.extent = "MAXOF"

            #intermediate formula plant

            # size = (capacity * 8760 * loadFactor)/(DNI * efficiency[counter-1])

            size1 = (capacity * 8760 * loadFactor)
            timesConstant = efficiency[counter-1]
            size2 = Times(3, timesConstant)
            print size2
            size = Divide(size1, size2)

            # Calculate power block & storage              
            powerBlock = capacity * 1484.9918 * costReductionFactorPlant[counter-1]
            storage = storageHours * capacity * 39.45759 * costReductionFactorPlant[counter-1]

            # Calculate mirrowField 
            # mirrorField = size * 155.6975 * costReductionFactorPlant[cont-1]
            timesConstant2 = costReductionFactorPlant[counter-1]
            inconstant = Times(155.6975, timesConstant2)
            mirrorField = Times(size, inconstant)

            # calculate PowerTower
            powerTower = ((capacity * 121.03883) + (capacity * 128.50378)) * costReductionFactorPlant[counter-1]

            # Calculate investmentPlant
            investmentPlant = powerBlock + storage + mirrorField + powerTower

            # Calculate omPlant
            omPlant = Times(investmentPlant, 0.048)

            #formula: lcoePlant = ((investmentPlant * (((i * (1 + i)^counter)/((1 + i)^counter-1))+ ir))+omPlant)/productionPlant*100
            # Formula Part 1 = (investmentPlant * (((i * (1 + i)^counter) Power symbol = **
            InConstant3= i * ((1 + i)**counter)
            FormulaPart1 = Times(investmentPlant, InConstant3)

            # Formula Part 2 = ((1 + i)^counter-1))+ ir))+omPlant)/productionPlant*100
            FormulaPart2 =(((1 + i)**(counter-1)+ ir)+omPlant)/productionPlant*100

            # Formula
            lcoePlant = Divide(FormulaPart1, FormulaPart2)

            lcoePlantTotal = lcoePlantTotal + lcoePlant

            lcoePlantTotal.save = "D:\\02_ArcGIS\\Python" + str(lcoePlantTotal) + ".img"

print "lcoePlanttotal calculated"

Answer 1

You need to escape your backslashes, you can see how it thinks you are saying hex-2. If you look at the final line in your error msg, it's telling you the file doesn't exist and it's showing that it has a different file name from what you had given.

>>> DNI =  "D:\02_ArcGIS\Python\LCOE_test"
>>> DNI
'D:\x02_ArcGIS\\Python\\LCOE_test'

>>> DNI =  "D:\\02_ArcGIS\\Python\\LCOE_test"
>>> DNI
'D:\\02_ArcGIS\\Python\\LCOE_test'
>>> print DNI
D:\02_ArcGIS\Python\LCOE_test