appending pandas columns data-CodePudding

why can't the pandas data frame append appropriately to form one data frame in this loop?

#Produce the overall data frame
def processed_data(data1_,f_loc,open,close):
    """data1_: is the csv file to be modified
    f_loc: is the location of csv files to be processed
    open and close: are the columns to undergo computations
    
    returns a new dataframe of modified columns"""
    main_file=drop_col(data1_)#Dataframe to append more data columns to
    for i in files_path(f_loc):
        data=get_data_frame(i[0])#returns the dataframe, takes file path location of the csv file and returns the data frame
        perc=perc_df(data,open,close,i[1])#Dataframe to append
        copy_data=main_file.append(perc)
    
    
    return copy_data

heres the output:

          Date  WTRX-USD
0   2021-05-27       NaN
1   2021-05-28       NaN
2   2021-05-29       NaN
3   2021-05-30       NaN
4   2021-05-31       NaN
..         ...       ...
79         NaN -2.311576
80         NaN  5.653349
81         NaN  5.052950
82         NaN -2.674435
83         NaN -3.082957

[450 rows x 2 columns]

My intention is to return something like this(where each append operation adds a column):

           Date      Open      High       Low     Close  Adj Close    Volume
0    2021-05-27  0.130793  0.136629  0.124733  0.128665   0.128665  70936563
1    2021-05-28  0.128659  0.129724  0.111244  0.113855   0.113855  71391441
2    2021-05-29  0.113752  0.119396  0.108206  0.111285   0.111285  62049940
3    2021-05-30  0.111330  0.115755  0.107028  0.112185   0.112185  70101821
4    2021-05-31  0.112213  0.126197  0.111899  0.125617   0.125617  83502219
..          ...       ...       ...       ...       ...        ...       ...
361  2022-05-23  0.195637  0.201519  0.185224  0.185231   0.185231  47906144
362  2022-05-24  0.185242  0.190071  0.181249  0.189553   0.189553  33312065
363  2022-05-25  0.189550  0.193420  0.183710  0.183996   0.183996  33395138
364  2022-05-26  0.184006  0.186190  0.165384  0.170173   0.170173  57218888
365  2022-05-27  0.170636  0.170660  0.165052  0.166864   0.166864  63560568

[366 rows x 7 columns]

CodePudding user response：

pandas.concat

pandas.DataFrame.append has been deprecated. Use pandas.concat instead.

Combine DataFrame objects horizontally along the x-axis by passing in axis=1

copy_data=pd.concat([copy_data,perc], axis=1)