Generate Pandas DataFrames from CSV file list - python

To frame the question. I am searching a directory for all csv files. I am saving the path of each csv file along with the delineation into a DataFrame. I know want to iterate over the DataFrame, and read in the specific csv file into a dataframe with a name generated from the original filename. I cannot figure out how to dynamically generate these dataframes. I started coding a few days ago so apologies if the syntax is poor.
# Looks in a given directory and all subsequent subdirectories for the extension ".csv"
# Reads path to all csv files and creates a list
PATH = "Z:\Adam"
EXT = "*.csv"
all_csv_files = [file
for path, subdir, files in os.walk(PATH)
for file in glob(os.path.join(path, EXT))]
# The list of csv file directories is read into a DataFrame
# Dataframe is then split into columns based on the \\ found in the path
df_csv_path = pd.DataFrame(all_csv_files, columns =['Path'])
df_split_path = df_csv_path['Path'].str.split('\\', n = -1, expand = True)
df_split_path = df_split_path.rename(columns = {0:'Drive',1:'Main',2:'Project',3:'Imaging Folder', 4:'Experimental Group',5:'Experimental Rep',6:'File Name'})
df_csv_info = df_split_path.join(df_csv_path['Path'])
# Generates a Dataframe for each of the csv files found in directory
# Dataframe has a name based on the csv filename
for index in df_csv_info.index:
filepath = ""
filename = df_csv_info['File Name'].values[index]
filepath = str(df_csv_info['Path'].values[index])
filename = pd.read_csv(filepath)

The best way is to create a dictionary whose keys are the filenames and the values are the corresponding DataFrame. Instead of using os.path and glob, the modern approach is to use pathlib from the standard library.
Assuming that you don't actually need the DataFrame containing the filenames and just want the DataFrames for each csv file, you can simply do
from pathlib import Path
PATH = Path("Z:\Adam")
EXT = "*.csv"
# dictionary holding all the files DataFrames with the format {"filename": file_DataFrame}
files_dfs = {}
# recursive search for csv files in PATH folder and subfolders
for csv_file in PATH.rglob(EXT):
filename = csv_file.name # get the filename
df = pd.read_csv(csv_file) # read the csv file as a DataFrame
files_dfs[filename] = df # add the DataFrame to the dictionary
Then, to access the DataFrame of a specific file you can do
filename_df = files_dfs["<filename>"]

Related

How to upload all csv files that have specific name inside filename in python

I want to concat all csv file that have this specific word 'tables' on the filename.
Below code is upload all csv file without filter the specific word that i want.
# importing the required modules
import glob
import pandas as pd
# specifying the path to csv files
#path = "csvfoldergfg"
path = "folder_directory"
# csv files in the path
files = glob.glob(path + "/*.csv")
# defining an empty list to store
# content
data_frame = pd.DataFrame()
content = []
# checking all the csv files in the
# specified path
for filename in files:
# reading content of csv file
# content.append(filename)
df = pd.read_csv(filename, index_col=None)
content.append(df)
# converting content to data frame
data_frame = pd.concat(content)
print(data_frame)
example filename are:
abcd-tables.csv
abcd-text.csv
abcd-forms.csv
defg-tables.csv
defg-text.csv
defg-forms.csv
From the example filenames. The expected output is concat filenames
abcd-tables.csv
defg-tables.csv
into single dataframe. Assuming the header are same.
*Really appreciate you guys can solve this
You can use:
import pandas as pd
import pathlib
path = 'folder_directory'
content = []
for filename in pathlib.Path(path).glob('*-tables.csv'):
df = pd.read_csv(filename, index_col=None)
content.append(df)
df = pd.concat(content, ignore_index=True)

Iterating through txt files in directory, saving filenames

I'm iterating through files in a directory and would like to save the filename and some stuff I extract from the files in the same pandas dataframe. How can I save the names the txt files in a list (which I would then insert into pandas dataframe as a separate column) while going through all the files in a directory?
Here's part of my code:
columns_df = ['file', 'stuff']
df_stuff = pd.DataFrame(columns = columns_df)
filenamelist = []
stufflist = []
os.chdir(r'path\to\directory')
for file in glob.glob('*.txt'):
# Extract some stuff from file and append to stufflist (DONE)
# Save filename in the filenamelist (THE PROBLEM)
df_stuff['stuff'] = stufflist
df_stuff['file'] = filenamelist
Do you need this functionality?
for file in glob.glob('*.txt'):
filenamelist.append(file)

How can I read any excel file with pandas which is in folder?

I am having a folder d:/data/input where I have an excel file stored. I want to read the excel file into a dataframe with pandas WITHOUT declaring the excel filename. Is that possible?
Thanks for your help.
If it's the only Excel file in the folder, you could do something like:
from pathlib import Path
fn = list(Path("D:/data/input").glob("*.xlsx"))[0]
df = pd.read_excel(fn)
If there's more than one file there, it'll end up just picking one of them arbitrarily, so probably not ideal.
Whatever you have in this folder path, you can do what you request for only one Excels files or as many Excels files you want by this way bellow, not the most elegant, for sure, but it work and it is flexible:
import pandas as pd
from os import listdir
from os.path import isfile, join
sourcePath = r"d:/data/input"
extensionFile = r".xlsx"
# Get all files in the path
fileNameList = [f for f in listdir(sourcePath) if isfile(join(sourcePath, f))]
# Removing all non excel (.xlsx) files from the list
fileNameList = [x for x in fileNameList if extensionFile in x]
# For accessing only one "first" file
print(fileNameList[0], "is loaded!") # Print the name as reference if you want to
df = pd.read_excel(sourcePath + r"/" +fileNameList[0])
# For loading all files into a list or dict
dataframeList = []
for fn in fileNameList:
dataframeList.append([pd.read_excel(sourcePath + r"/" + fn)])
# To access each data frame
fileNameList[0] # Print the name as reference if you want
dataframeList[0]
# call the seconde
fileNameList[1] # Print the name as reference if you want
dataframeList[1]
# call the third
fileNameList[2] # Print the name as reference if you want
dataframeList[2]
# call the ...
fileNameList[...]
dataframeList[...]
If there are multiple excel files we could get the file with the latest create time :
from pathlib import Path
def get_latest_excel(src):
""" src : source path to target files"""
dfs = {f.stat().st_ctime : f for f in Path(src).glob('*.xlsx')}
return dfs[max(dfs, key=dfs.get)]
file = get_latest_excel(r"d:/data/input")
print(file)
WindowsPath('d:/data/input/new_excel_file.xlsx')
df = pd.read_excel(file)

How to match the .mp4 files present in a folder with the names in .csv file and sort according to some column value, in python?

I have a folder containing about 500 .mp4 files :
abc.mp4
lmn.mp4
ijk.mp4
Also I have a .csv file containing the file names (>500) and some values associated with them:
file name value
abc.mp4 5
xyz.mp4 3
lmn.mp4 5
rgb.mp4 4
I want to match the file names of .csv and folder and then place the mp4 files in separate folders depending on the value.
**folder 5:**
abc.mp4
lmn.mp4
**folder 3:**
xyz.mp4
and so on
I tried link
names=[]
names1=[]
for dirname, dirnames, filenames in os.walk('./videos_test'):
for filename in filenames:
if filename.endswith('.mp4'):
names.append(filename)
file = open('names.csv',encoding='utf-8-sig')
lns = csv.reader(file)
for line in lns:
nam = line [0]
sc=line[1]
names1.append(nam)
if nam in names:
print (nam, line[1])
if line[1]==5
print ('5')
print(nam) %just prints the name of file not save
else if line[1]==3
print ('3')
print(nam)
does not give any result.
I'd recommend you to use pandas if you're going to handle csv files.
Here's a code that will automatically create the folders, and put the files in the right place for you using shutil and pandas. I have assumed that your csv's columns are "filename" and "value". Change them if there's a mismatch.
import pandas as pd
import shutil
import os
path_to_csv_file = "file.csv"
df = pd.read_csv(path_to_csv_file)
mp4_root = "mp4_root"
destination_path = "destination_path"
#In order to remove the folder if previously created. You can delete this if you don't like it.
if os.path.isdir(destination_path):
shutil.rmtree(destination_path)
os.mkdir(destination_path)
unique_values = pd.unique(df['value'])
for u in unique_values:
os.mkdir(os.path.join(destination_path, str(u)))
#Here we iterate over the rows of your csv file, and concatenate the value and the filename to the destination_path with our new folder structure.
for index, row in df.iterrows():
cur_path = os.path.join(destination_path, str(row['value']), str(row['filename']))
source_path = os.path.join(mp4_root, str(row['filename']))
shutil.copyfile(source_path, cur_path)
EDIT: If there's a file that is in the csv but not present in the source folder, you could check it before (more pythonic) or you could handle it via a try/catch exception check.(Not recommended)
Check the code below.
source_files = os.listdir(mp4_root)
for index, row in df.iterrows():
if str(row['filename']) not in source_files:
continue
cur_path = os.path.join(destination_path, str(row['value']), str(row['filename']))
source_path = os.path.join(mp4_root, str(row['filename']))
shutil.copyfile(source_path, cur_path)

How to merge 2000 CSV files saved in different subfolders within the same main folder

Hey People I would like to merge 2000 Csv files into one of 2000 sub-folders. Each sub-folder contains three Csv files with different names. so I need to select only one Csv from each folder.
I know the code for how to merge bunch of Csv files if they are in the same - folder.
import pandas as pd
import glob
path = r'Total_csvs'
all_files = glob.glob(path + "/*.csv")
li = []
for filename in all_files:
df = pd.read_csv(filename, index_col=None, header=0)
li.append(df)
frame = pd.concat(li, axis=0, ignore_index=True)
frame.to_csv('Total.csv',index=False)
But my problems with 2000 Csv files look totally different.
Folder structure is:
Main folder (with in this 2000 subfolders, within subfolders I had multiple Csv Files and I need to select only one Csv file from this. Finally concating all 2000 Csv files.)
Coming to Naming Conventions (all the subfolders had different names, but the subfolder name and the Csv name within the subfolder is same)
Any suggestions or a sample code (how to read 2000 Csv from sub-folders) would be helpful.
Thanks in advance
You can loop through all the subfolders using os.listdir.
Since the CSV filename is the same as the subfolder name, simply use the subfolder name to construct the full path name.
import os
import pandas
folders = os.listdir("Total_csvs")
li = []
for folder in folders:
# Since they are the same name
selected_csv = folder
filename = os.path.join(folder, selected_csv + ".csv")
df = pd.read_csv(filename, index_col=None, header=0)
li.append(df)
frame = pd.concat(li, axis=0, ignore_index=True)
frame.to_csv('Total.csv',index=False)
We can iterate on every subfolder, determine expected_csv_path, check if it exists. If it exists, we add them to our all_files list.
Try following:
import pandas as pd
import os
path = r'Total_csvs'
li = []
for f in os.listdir(path):
expected_csv_path = os.path.join(path, f, f + '.csv')
csv_exists = os.path.isfile(expected_csv_path)
if csv_exists:
df = pd.read_csv(expected_csv_path, index_col=None, header=0)
li.append(df)
frame = pd.concat(li, axis=0, ignore_index=True, sort=False)
frame.to_csv('Total.csv',index=False)
If you are using Python 3.5 or newer you could use glob.glob in recursive manner following way:
import glob
path = r'Total_csvs'
all_csv = glob.glob(path+"/**/*.csv",recursive=True)
Now all_csv is list of relative paths to all *.csv inside Total_csv and subdirectories of Total_csv and subdirectories of subdirectories of Total_csv and so on.
For example purpose lets assume that all_csv is now:
all_csv = ['Total_csvs/abc/abc.csv','Total_csv/abc/another.csv']
So we need to get files with names correnponding to directory of their residence, this could be done following way:
import os
def check(x):
directory,filename = x.split(os.path.sep)[-2:]
return directory+'.csv'==filename
all_csv = [i for i in all_csv if check(i)]
print(all_csv) #prints ['Total_csvs/abc/abc.csv']
Now all_csv is list of paths to all .csv you are seeking and you can use it same way as you did with all_csv in "flat" (non-recursive) case.
You can do it without joining paths:
import pathlib,pandas
lastparent=None
for ff in pathlib.Path("Total_csvs").rglob("*.csv"): # recursive glob
print(ff)
if(ff.parent!=lastparent): # process the 1st file in the dir
lastparent= ff.parent
df = pd.read_csv(str(ff),... )
...etc.

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