import pandas as pd df = pd.read_csv("exploratoryTool/data/DATABASE_LG_reqs_HH_pass2.csv", index_col=None) # for all rows: # subtract 0.5 from xfrom # subtract 0.5 from yfrom # if xto is empty, add 1 to xfrom else add 0.5 # if yto is empty, add 1 to yfrom else add 0.5 df["xfrom"] -= 0.5 df["yfrom"] -= 0.5 xto_isempty = df["xto"].isna() df.loc[xto_isempty,"xto"] = df.loc[xto_isempty, "xfrom"] + 1 df.loc[~xto_isempty,"xto"] += 0.5 yto_isempty = df["yto"].isna() df.loc[yto_isempty,"yto"] = df.loc[yto_isempty, "yfrom"] + 1 df.loc[~yto_isempty,"yto"] += 0.5 print(df.head()) df.to_csv("exploratoryTool/data/DATABASE.csv", index=False, encoding="utf8")