python add rows in dataframe based on a condition of another column

Question

What I have:

df = pd.DataFrame(data = ["version11.11","version2.2","version3"], columns=["software_version"])


  Index software_version
    0   version11.11
    1   version2.2
    2   version3

What I am trying to do:

Is to detect the type of the second last character in the dataframe column called software_version and create a new column in the dataframe based on that condition.

If the second last character is a digit or an alphabet, extract the whole name without the last alpha/digital. Such as version11.11 becomes version11.1 OR version3 becomes version. elif, its a decimal place then extract til before the decimal place, version2.2 becomes version2

Output Should be:

  Index software_version  main_software
    0   version11.11     version11.1
    1   version2.2       version2
    2   version3         version

What I did so far:

How can I cleanly add the column above main_software ?

import pandas as pd

df = pd.DataFrame(data = ["version11.11","version2.2","version3"], columns=["software_version"])

for name in df.software_version:
    if name[-2].isalnum():
        print(name[:-1])

    elif name[-2] == ".":
        print(name[:-2])

    else :
        print("!Alphanum-dot")

Sruthi · Accepted Answer · 2018-12-02 10:49:57Z

1

You can first define a function that makes the necessary changes on the string.

def GetMainSoftware(string):
    new_string=string[:-1] #first remove the last character
    if(new_string[-1]=="."): #if "." is present, remove that too
        return new_string[:-1]
    else:
        return new_string

And then use apply on the dataframe to create a new column with these specifics.

df["main_software"]=df.apply(lambda row: GetMainSoftware(row["software_version"]),axis=1)

df will now be :

  software_version main_software
0     version11.11   version11.1
1       version2.2      version2
2         version3       version

answered Dec 2, 2018 at 10:49

Sruthi

3,0281 gold badge14 silver badges26 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

python add rows in dataframe based on a condition of another column

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related