带有“（）”的化学式如何分解成它们的组成元素？

Question

I wanto to create constituent elements dataset from chemical formulas. I was able to break down the chemical formulas without the (), but I am unable to write the code for the ones with the ().

The code without () is below.

symbol = ''
comp_list = []
wt_list = []
for c in chemical_formula:
    if c.isupper():
        if len(symbol) != 0:
            comp_list.append(symbol)
            wt_list.append(1)
            symbol = ''
        symbol += c
    elif c.islower():
        symbol += c
    else:
        comp_list.append(symbol)
        wt_list.append(int(c))
        symbol = ''
    
if len(symbol) != 0:
    comp_list.append(symbol)
    wt_list.append(1)

comp_data[atom_cols] = comp_list
comp_data[comp_cols] = wt_list

and for example, I want to split chemical formula 'Ti3(SbPd)2' into below.

M1	M2	M3	M1_num	M2_num	M3_num
Ti	Sb	Pd	3	2	2

Answer 1

I didn't want to change your code, so in that case we have to return the string with "parenthesis" without it. For this, I had to put your code in an "if" of my "for". However, I don't think we have reached a very optimized solution: (:

chemical_formula1 = 'Cu3(PO4)2'

chF = ''
parentheses = False
add_parentheses = False

chemical_formula = ''
symbol = ''
comp_list = []
wt_list = []


for i in chemical_formula1:

  #====================================================================================================
  if i == ')' :
    parentheses = False
    add_parentheses = True

  elif i == '(' :
    parentheses = True

  elif parentheses == True:
    chemical_formula += str(i)
  #====================================================================================================


  #==================== Adding the elements inside the '()' while "i" is the number after the ')' ====================
  elif add_parentheses == True:
    #==================== YOUR CODE TO BREAK CHEMICAL FORMULA ====================
    for c in chemical_formula:
        if c.isupper():
            if len(symbol) != 0:
                comp_list.append(symbol)
                wt_list.append(1)
                symbol = ''
            symbol += c
        elif c.islower():
            symbol += c
        else:
            comp_list.append(symbol)
            wt_list.append(int(c))
            symbol = ''
        
    if len(symbol) != 0:
        comp_list.append(symbol)
        wt_list.append(1)
    #===========================================================================
    for e in range(len(comp_list)):
      chF += str(comp_list[e])
      chF += str((int(wt_list[e]))*int(i))
    add_parentheses = False
  #==================================================================================================================================


  #==================== If we don't have any parentheses, only this "if" will be run every time ====================
  elif parentheses == False and add_parentheses == False:
    chF += str(i)
  #======================================================================================================================

print(chF)

Output:

Cu3P2O8