如何消除 UpdateCursor 上的 elif 语法错误？

Question

Why am I getting a Syntax error on elif when trying to calculate an index with the UpdateCursor function in Python? This is my code, the second elif always gives a syntax error.

    fc = 'Oberbodenproben_mit_Laborwerten_2019_1'
    fields = ['ABAG_K_Faktor','K1','K2','K3','T_proz','U_proz','S_proz','U+ffS_proz','S-ffS_proz','Org_Substanz_proz','Permeabilitätsklasse','Aggregierungsklasse','Steinbedeckung_proz']

Create update cursor for feature class

    with arcpy.da.UpdateCursor(fc, fields) as cursor:
        
# For each row, evaluate the WELL_YIELD value (index position 
# of 0), and update WELL_CLASS (index position of 1)

       for row in cursor:   

         if (row[7]<= 70):
           row[1] = 2.77*10**(-5) *((row[7]*(100-row[4]))**1.14
         elif(row[7] > 70):
           row[1] = 1.75*10**(-5)*((row[7]*(100-row[4]))**1.14+0.0024*row[8]+0,161
         elif (row[9] <= 4):
           row[2] = row[1]*(12-row[9])/10
         elif (row[9] > 4):
           row[2] = row[1]*0.8
         elif (row[2] >= 0.2):
           row[3] = row[2]+0.043*(row[11]-2)+0.033*(4-row[10])
         elif (row[2] < 0.2):
           row[3] = 0.091-0.34*row[2]+1.79*row[2]**2+0.24*row[2]*row[11]+0.033*(4-row[10])   
         elif (row[12]<=1,5):
           row[0]=row[3]
         elif (row[12]>1,5):
           row[0]=row[3]*(1.1*math.e**(-0.0024*row[12])-0.06)
               
    # Update the cursor with the updated list
    cursor.updateRow(row)

    return

I already tried getting read of the formulas, but with easy numbers another problem turns up. Apparently the rows don't exist then.

Answer 1

Indents matter for python code. And so do matching ( ) parens. Here is what you intended:

    for row in cursor:

        if row[7] <= 70:
            row[1] = 2.77 * 10 ** (-5) * ((row[7] * (100 - row[4])) ** 1.14)
        elif row[7] > 70:
            row[1] = (
                1.75
                * 10 ** (-5)
                * ((row[7] * (100 - row[4])) ** 1.14 + 0.0024 * row[8] + 0, 161)
            )
        elif row[9] <= 4:
            row[2] = row[1] * (12 - row[9]) / 10
        elif row[9] > 4:
            row[2] = row[1] * 0.8
        elif row[2] >= 0.2:
            row[3] = row[2] + 0.043 * (row[11] - 2) + 0.033 * (4 - row[10])
        elif row[2] < 0.2:
            row[3] = (
                0.091
                - 0.34 * row[2]
                + 1.79 * row[2] ** 2
                + 0.24 * row[2] * row[11]
                + 0.033 * (4 - row[10])
            )
        elif (row[12] <= 1, 5):
            row[0] = row[3]
        elif (row[12] > 1, 5):
            row[0] = row[3] * (1.1 * math.e ** (-0.0024 * row[12]) - 0.06)

1.75 * 10 ** (-5) is kind of a curious way to express the constant 1.75e-5 , but I guess it works for you so go for it.

---

Using the name of each field within a row would be much more readable than indexes like [12] .

Consider doing

from collections import namedtuple`

Foo = namedtuple("Foo", fields)

(It's not yet clear what each row represents -- choose a more descriptive name than Foo.)

https://docs.python.org/3/library/collections.html#collections.namedtuple