python: extract float from a python list of string( AUD 31.99)












2














python: extract float from a python list of string( AUD 31.99).
I used openpyxl to read from an excel file the amount list. and i saved it in a list but the list is in string form like this: 



['31.40 AUD', ' 32.99 AUD', '37.24 AUD']


I need to get the float from the string item list so that i can later save it in a new list to get the total of them.



Desired output:



[31.40, 32.99, 37.24]


I have already tried these:



newList = re.findall("d+.d+", tot[0])

print(newList)


Output:



[31.40]


But How can I use this for all the item elements?



I am new to python, this is just for some work i do, wanted to see the total using python instead of using excel`s find & replace option.
thanks






python regex excel list openpyxl







share|improve this question
























  • Take a look here: book.pythontips.com/en/latest/map_filter.html
    – Julio
    Nov 13 '18 at 8:24






  • 1




    You should do the conversion before creating the list.
    – Charlie Clark
    Nov 13 '18 at 8:25










  • You are close.. but you are just passing tot[0].
    – Anton vBR
    Nov 13 '18 at 8:26






  • 3




    try [item.split()[0] for item in ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']]
    – Andersson
    Nov 13 '18 at 8:26






  • 1




    Is it mandatory to use regex?
    – Vasilis G.
    Nov 13 '18 at 8:28
















2














python: extract float from a python list of string( AUD 31.99).
I used openpyxl to read from an excel file the amount list. and i saved it in a list but the list is in string form like this: 



['31.40 AUD', ' 32.99 AUD', '37.24 AUD']


I need to get the float from the string item list so that i can later save it in a new list to get the total of them.



Desired output:



[31.40, 32.99, 37.24]


I have already tried these:



newList = re.findall("d+.d+", tot[0])

print(newList)


Output:



[31.40]


But How can I use this for all the item elements?



I am new to python, this is just for some work i do, wanted to see the total using python instead of using excel`s find & replace option.
thanks






python regex excel list openpyxl







share|improve this question
























  • Take a look here: book.pythontips.com/en/latest/map_filter.html
    – Julio
    Nov 13 '18 at 8:24






  • 1




    You should do the conversion before creating the list.
    – Charlie Clark
    Nov 13 '18 at 8:25










  • You are close.. but you are just passing tot[0].
    – Anton vBR
    Nov 13 '18 at 8:26






  • 3




    try [item.split()[0] for item in ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']]
    – Andersson
    Nov 13 '18 at 8:26






  • 1




    Is it mandatory to use regex?
    – Vasilis G.
    Nov 13 '18 at 8:28














2












2








2







python: extract float from a python list of string( AUD 31.99).
I used openpyxl to read from an excel file the amount list. and i saved it in a list but the list is in string form like this: 



['31.40 AUD', ' 32.99 AUD', '37.24 AUD']


I need to get the float from the string item list so that i can later save it in a new list to get the total of them.



Desired output:



[31.40, 32.99, 37.24]


I have already tried these:



newList = re.findall("d+.d+", tot[0])

print(newList)


Output:



[31.40]


But How can I use this for all the item elements?



I am new to python, this is just for some work i do, wanted to see the total using python instead of using excel`s find & replace option.
thanks






python regex excel list openpyxl







share|improve this question















python: extract float from a python list of string( AUD 31.99).
I used openpyxl to read from an excel file the amount list. and i saved it in a list but the list is in string form like this: 



['31.40 AUD', ' 32.99 AUD', '37.24 AUD']


I need to get the float from the string item list so that i can later save it in a new list to get the total of them.



Desired output:



[31.40, 32.99, 37.24]


I have already tried these:



newList = re.findall("d+.d+", tot[0])

print(newList)


Output:



[31.40]


But How can I use this for all the item elements?



I am new to python, this is just for some work i do, wanted to see the total using python instead of using excel`s find & replace option.
thanks






python regex excel list openpyxl




python regex excel list openpyxl






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 13 '18 at 8:26









Vasilis G.

3,4082722




3,4082722










asked Nov 13 '18 at 8:22









Anamul ChoudhuryAnamul Choudhury

266




266












  • Take a look here: book.pythontips.com/en/latest/map_filter.html
    – Julio
    Nov 13 '18 at 8:24






  • 1




    You should do the conversion before creating the list.
    – Charlie Clark
    Nov 13 '18 at 8:25










  • You are close.. but you are just passing tot[0].
    – Anton vBR
    Nov 13 '18 at 8:26






  • 3




    try [item.split()[0] for item in ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']]
    – Andersson
    Nov 13 '18 at 8:26






  • 1




    Is it mandatory to use regex?
    – Vasilis G.
    Nov 13 '18 at 8:28


















  • Take a look here: book.pythontips.com/en/latest/map_filter.html
    – Julio
    Nov 13 '18 at 8:24






  • 1




    You should do the conversion before creating the list.
    – Charlie Clark
    Nov 13 '18 at 8:25










  • You are close.. but you are just passing tot[0].
    – Anton vBR
    Nov 13 '18 at 8:26






  • 3




    try [item.split()[0] for item in ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']]
    – Andersson
    Nov 13 '18 at 8:26






  • 1




    Is it mandatory to use regex?
    – Vasilis G.
    Nov 13 '18 at 8:28
















Take a look here: book.pythontips.com/en/latest/map_filter.html
– Julio
Nov 13 '18 at 8:24




Take a look here: book.pythontips.com/en/latest/map_filter.html
– Julio
Nov 13 '18 at 8:24




1




1




You should do the conversion before creating the list.
– Charlie Clark
Nov 13 '18 at 8:25




You should do the conversion before creating the list.
– Charlie Clark
Nov 13 '18 at 8:25












You are close.. but you are just passing tot[0].
– Anton vBR
Nov 13 '18 at 8:26




You are close.. but you are just passing tot[0].
– Anton vBR
Nov 13 '18 at 8:26




3




3




try [item.split()[0] for item in ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']]
– Andersson
Nov 13 '18 at 8:26




try [item.split()[0] for item in ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']]
– Andersson
Nov 13 '18 at 8:26




1




1




Is it mandatory to use regex?
– Vasilis G.
Nov 13 '18 at 8:28




Is it mandatory to use regex?
– Vasilis G.
Nov 13 '18 at 8:28












4 Answers
4






active

oldest

votes


















1














You can use the map function:



inList = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']

output = list(map(lambda elem: float(elem.split()[0]), inList))

print(output)


Output:



[31.4, 32.99, 37.24]





share|improve this answer





















  • This one solved the problem, Thanks alot.
    – Anamul Choudhury
    Nov 13 '18 at 8:36










  • @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
    – Vasilis G.
    Nov 13 '18 at 8:48



















1














If you want to get list of values with regex, try



tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']

newList = [float(re.search('d+.d+', fl).group(0)) for fl in tot]

print(newList)

# [31.40, 32.99, 37.24]


but using split seem to be easier solution in this case 



tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']

newList = [float(item.split()[0]) for item in tot] 

print(newList)

# [31.40, 32.99, 37.24]


If second substring is always the same ("AUD") you can also try



tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']

newList = [float(item.rstrip(' AUD')) for item in tot] 

print(newList)

# [31.40, 32.99, 37.24]





share|improve this answer































    0














    Is it possible to use a string split instead? I think it would be much simpler 



    ls1 = ['32.46 AUD', '17.34 AUD']
    

    
myFloats = 
    
for aString in ls1:
    
    aFloat = float(aString.split()[0])
    
    myFloats.append(aFloat)





    share|improve this answer





























      0














      You should consider handling errors. Here is one way for instance:



      import re
      
import math
      

      
def float_from_string(str_):
      
    # Try to extract a floating number, if fail return nan
      
    r = re.search('d+.d+', str_)
      
    return float(r.group()) if r else math.nan
      

      
tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD', ' nonumberhere AUD']
      
totfloat = [float_from_string(i) for i in tot]
      

      
print(totfloat)


      Returns:



      [31.4, 32.99, 37.24, nan]





      share|improve this answer





















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        4 Answers
        4






        active

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        4 Answers
        4






        active

        oldest

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        active

        oldest

        votes






        active

        oldest

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        1














        You can use the map function:



        inList = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
output = list(map(lambda elem: float(elem.split()[0]), inList))
        
print(output)


        Output:



        [31.4, 32.99, 37.24]





        share|improve this answer





















        • This one solved the problem, Thanks alot.
          – Anamul Choudhury
          Nov 13 '18 at 8:36










        • @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
          – Vasilis G.
          Nov 13 '18 at 8:48
















        1














        You can use the map function:



        inList = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
output = list(map(lambda elem: float(elem.split()[0]), inList))
        
print(output)


        Output:



        [31.4, 32.99, 37.24]





        share|improve this answer





















        • This one solved the problem, Thanks alot.
          – Anamul Choudhury
          Nov 13 '18 at 8:36










        • @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
          – Vasilis G.
          Nov 13 '18 at 8:48














        1












        1








        1






        You can use the map function:



        inList = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
output = list(map(lambda elem: float(elem.split()[0]), inList))
        
print(output)


        Output:



        [31.4, 32.99, 37.24]





        share|improve this answer












        You can use the map function:



        inList = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
output = list(map(lambda elem: float(elem.split()[0]), inList))
        
print(output)


        Output:



        [31.4, 32.99, 37.24]






        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Nov 13 '18 at 8:31









        Vasilis G.Vasilis G.

        3,4082722




        3,4082722












        • This one solved the problem, Thanks alot.
          – Anamul Choudhury
          Nov 13 '18 at 8:36










        • @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
          – Vasilis G.
          Nov 13 '18 at 8:48


















        • This one solved the problem, Thanks alot.
          – Anamul Choudhury
          Nov 13 '18 at 8:36










        • @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
          – Vasilis G.
          Nov 13 '18 at 8:48
















        This one solved the problem, Thanks alot.
        – Anamul Choudhury
        Nov 13 '18 at 8:36




        This one solved the problem, Thanks alot.
        – Anamul Choudhury
        Nov 13 '18 at 8:36












        @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
        – Vasilis G.
        Nov 13 '18 at 8:48




        @AnamulChoudhury you're welcome. Feel free to accept it as an answer if it helped you :)
        – Vasilis G.
        Nov 13 '18 at 8:48













        1














        If you want to get list of values with regex, try



        tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
newList = [float(re.search('d+.d+', fl).group(0)) for fl in tot]
        
print(newList)
        
# [31.40, 32.99, 37.24]


        but using split seem to be easier solution in this case 



        tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
newList = [float(item.split()[0]) for item in tot] 
        
print(newList)
        
# [31.40, 32.99, 37.24]


        If second substring is always the same ("AUD") you can also try



        tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
        
newList = [float(item.rstrip(' AUD')) for item in tot] 
        
print(newList)
        
# [31.40, 32.99, 37.24]





        share|improve this answer




























          1














          If you want to get list of values with regex, try



          tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
          
newList = [float(re.search('d+.d+', fl).group(0)) for fl in tot]
          
print(newList)
          
# [31.40, 32.99, 37.24]


          but using split seem to be easier solution in this case 



          tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
          
newList = [float(item.split()[0]) for item in tot] 
          
print(newList)
          
# [31.40, 32.99, 37.24]


          If second substring is always the same ("AUD") you can also try



          tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
          
newList = [float(item.rstrip(' AUD')) for item in tot] 
          
print(newList)
          
# [31.40, 32.99, 37.24]





          share|improve this answer


























            1












            1








            1






            If you want to get list of values with regex, try



            tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
            
newList = [float(re.search('d+.d+', fl).group(0)) for fl in tot]
            
print(newList)
            
# [31.40, 32.99, 37.24]


            but using split seem to be easier solution in this case 



            tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
            
newList = [float(item.split()[0]) for item in tot] 
            
print(newList)
            
# [31.40, 32.99, 37.24]


            If second substring is always the same ("AUD") you can also try



            tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
            
newList = [float(item.rstrip(' AUD')) for item in tot] 
            
print(newList)
            
# [31.40, 32.99, 37.24]





            share|improve this answer














            If you want to get list of values with regex, try



            tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
            
newList = [float(re.search('d+.d+', fl).group(0)) for fl in tot]
            
print(newList)
            
# [31.40, 32.99, 37.24]


            but using split seem to be easier solution in this case 



            tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
            
newList = [float(item.split()[0]) for item in tot] 
            
print(newList)
            
# [31.40, 32.99, 37.24]


            If second substring is always the same ("AUD") you can also try



            tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD']
            
newList = [float(item.rstrip(' AUD')) for item in tot] 
            
print(newList)
            
# [31.40, 32.99, 37.24]






            share|improve this answer














            share|improve this answer



            share|improve this answer








            edited Nov 13 '18 at 8:39

























            answered Nov 13 '18 at 8:33









            AnderssonAndersson

            37.6k103266




            37.6k103266























                0














                Is it possible to use a string split instead? I think it would be much simpler 



                ls1 = ['32.46 AUD', '17.34 AUD']
                

                
myFloats = 
                
for aString in ls1:
                
    aFloat = float(aString.split()[0])
                
    myFloats.append(aFloat)





                share|improve this answer


























                  0














                  Is it possible to use a string split instead? I think it would be much simpler 



                  ls1 = ['32.46 AUD', '17.34 AUD']
                  

                  
myFloats = 
                  
for aString in ls1:
                  
    aFloat = float(aString.split()[0])
                  
    myFloats.append(aFloat)





                  share|improve this answer
























                    0












                    0








                    0






                    Is it possible to use a string split instead? I think it would be much simpler 



                    ls1 = ['32.46 AUD', '17.34 AUD']
                    

                    
myFloats = 
                    
for aString in ls1:
                    
    aFloat = float(aString.split()[0])
                    
    myFloats.append(aFloat)





                    share|improve this answer












                    Is it possible to use a string split instead? I think it would be much simpler 



                    ls1 = ['32.46 AUD', '17.34 AUD']
                    

                    
myFloats = 
                    
for aString in ls1:
                    
    aFloat = float(aString.split()[0])
                    
    myFloats.append(aFloat)






                    share|improve this answer












                    share|improve this answer



                    share|improve this answer










                    answered Nov 13 '18 at 8:28









                    DavidhallDavidhall

                    259




                    259























                        0














                        You should consider handling errors. Here is one way for instance:



                        import re
                        
import math
                        

                        
def float_from_string(str_):
                        
    # Try to extract a floating number, if fail return nan
                        
    r = re.search('d+.d+', str_)
                        
    return float(r.group()) if r else math.nan
                        

                        
tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD', ' nonumberhere AUD']
                        
totfloat = [float_from_string(i) for i in tot]
                        

                        
print(totfloat)


                        Returns:



                        [31.4, 32.99, 37.24, nan]





                        share|improve this answer


























                          0














                          You should consider handling errors. Here is one way for instance:



                          import re
                          
import math
                          

                          
def float_from_string(str_):
                          
    # Try to extract a floating number, if fail return nan
                          
    r = re.search('d+.d+', str_)
                          
    return float(r.group()) if r else math.nan
                          

                          
tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD', ' nonumberhere AUD']
                          
totfloat = [float_from_string(i) for i in tot]
                          

                          
print(totfloat)


                          Returns:



                          [31.4, 32.99, 37.24, nan]





                          share|improve this answer
























                            0












                            0








                            0






                            You should consider handling errors. Here is one way for instance:



                            import re
                            
import math
                            

                            
def float_from_string(str_):
                            
    # Try to extract a floating number, if fail return nan
                            
    r = re.search('d+.d+', str_)
                            
    return float(r.group()) if r else math.nan
                            

                            
tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD', ' nonumberhere AUD']
                            
totfloat = [float_from_string(i) for i in tot]
                            

                            
print(totfloat)


                            Returns:



                            [31.4, 32.99, 37.24, nan]





                            share|improve this answer












                            You should consider handling errors. Here is one way for instance:



                            import re
                            
import math
                            

                            
def float_from_string(str_):
                            
    # Try to extract a floating number, if fail return nan
                            
    r = re.search('d+.d+', str_)
                            
    return float(r.group()) if r else math.nan
                            

                            
tot = ['31.40 AUD', ' 32.99 AUD', '37.24 AUD', ' nonumberhere AUD']
                            
totfloat = [float_from_string(i) for i in tot]
                            

                            
print(totfloat)


                            Returns:



                            [31.4, 32.99, 37.24, nan]






                            share|improve this answer












                            share|improve this answer



                            share|improve this answer










                            answered Nov 13 '18 at 8:37









                            Anton vBRAnton vBR

                            11.3k21022




                            11.3k21022






























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                                Bressuire

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                                Subprefecture and commune in Nouvelle-Aquitaine, France Bressuire Subprefecture and commune Chateau de Bressuire and the Eglise Notre-Dame Coat of arms Location of Bressuire Bressuire Show map of France Bressuire Show map of Nouvelle-Aquitaine Coordinates: 46°50′27″N 0°29′14″W  /  46.8408°N 0.4872°W  / 46.8408; -0.4872 Coordinates: 46°50′27″N 0°29′14″W  /  46.8408°N 0.4872°W  / 46.8408; -0.4872 Country France Region Nouvelle-Aquitaine Department Deux-Sèvres Arrondissement Bressuire Canton Bressuire Government  • Mayor .mw-parser-output .nobold{font-weight:normal} (2014–20) Jean Michel Bernier Area 1 180.59 km 2 (69.73 sq mi) Population (2014) 2 19,300  • Density 110/km 2 (280/sq mi) Time zone UTC+01:00 (CET)  • Summer (DST) UTC+02:00 (CEST) INSEE/Postal code 79049 /79300 Elevation 98–236 m (322–774 ft) (avg. 173 m or 568 ft) 1 French Land Register data, which exclude...
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                                Vorschmack

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                                Vorschmack Ukrainian Jewish-style vorschmack served on rye bread Course Hors d'oeuvre Region or state Eastern Europe Associated national cuisine Ashkenazi Jewish, Finnish, German, Ukrainian, Polish, Russian Main ingredients Ground meat and/or fish Cookbook: Vorschmack   Media: Vorschmack Vorschmack or forshmak (Yiddish: פֿאָרשמאַק ‎, from archaic German Vorschmack , "foretaste" [1] or "appetizer" [2] ) is an originally East European dish made of salty minced fish or meat. Different variants of this dish are especially common in Ashkenazi Jewish and Finnish cuisine. Some varieties are also known in Russian and Polish cuisine. Contents 1 In Jewish cuisine 2 In Russian cuisine 3 In Polish cuisine 4 In Finnish cuisine 5 See also 6 References In Jewish cuisine According to Gil Marks, the German name points to the possible Germanic origin of this dish. [1] William Pokhlyobkin descr...
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                                Quarantine

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                                For other uses, see Quarantine (disambiguation). Signal flag "Lima" called the "Yellow Jack" which when flown in harbor means ship is under quarantine. A simple yellow flag (also called the "Yellow Jack") had historically been used to signal quarantine (it stands for Q among signal flags), but now indicates the opposite, as a signal of a ship free of disease that requests boarding and inspection. A quarantine is used to separate and restrict the movement of people; it is 'a restraint upon the activities or communication of persons or the transport of goods designed to prevent the spread of disease or pests', for a certain period of time. [1] This is often used in connection to disease and illness, such as those who may possibly have been exposed to a communicable disease. [2] The term is often erroneously used to mean medical isolation, which is "to separate ill persons who have a communicable disease from those who are healthy...
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