pandas read_excel multiple tables on the same sheet
First read in the entire csv
file:
import pandas as pd
df = pd.read_csv('path_to\\your_data.csv')
and then obtain the individual frames, for example using:
df1 = df.iloc[:100,:]
df2 = df.iloc[100:200,:]
I wrote the following code to identify the multiple tables automatically, in case you have many files you need to process and don't want to look in each one to get the right row numbers. The code also looks for non-empty rows above each table and reads those as table metadata.
def parse_excel_sheet(file, sheet_name=0, threshold=5):
'''parses multiple tables from an excel sheet into multiple data frame objects. Returns [dfs, df_mds], where dfs is a list of data frames and df_mds their potential associated metadata'''
xl = pd.ExcelFile(file)
entire_sheet = xl.parse(sheet_name=sheet_name)
# count the number of non-Nan cells in each row and then the change in that number between adjacent rows
n_values = np.logical_not(entire_sheet.isnull()).sum(axis=1)
n_values_deltas = n_values[1:] - n_values[:-1].values
# define the beginnings and ends of tables using delta in n_values
table_beginnings = n_values_deltas > threshold
table_beginnings = table_beginnings[table_beginnings].index
table_endings = n_values_deltas < -threshold
table_endings = table_endings[table_endings].index
if len(table_beginnings) < len(table_endings) or len(table_beginnings) > len(table_endings)+1:
raise BaseException('Could not detect equal number of beginnings and ends')
# look for metadata before the beginnings of tables
md_beginnings = []
for start in table_beginnings:
md_start = n_values.iloc[:start][n_values==0].index[-1] + 1
md_beginnings.append(md_start)
# make data frames
dfs = []
df_mds = []
for ind in range(len(table_beginnings)):
start = table_beginnings[ind]+1
if ind < len(table_endings):
stop = table_endings[ind]
else:
stop = entire_sheet.shape[0]
df = xl.parse(sheet_name=sheet_name, skiprows=start, nrows=stop-start)
dfs.append(df)
md = xl.parse(sheet_name=sheet_name, skiprows=md_beginnings[ind], nrows=start-md_beginnings[ind]-1).dropna(axis=1)
df_mds.append(md)
return dfs, df_mds
Assuming we have the following Excel file:
Solution: we are parsing the first sheet (index: 0
)
xl = pd.ExcelFile(fn)
nrows = xl.book.sheet_by_index(0).nrows
df1 = xl.parse(0, skipfooter= nrows-(10+1)).dropna(axis=1, how='all')
df2 = xl.parse(0, skiprows=12).dropna(axis=1, how='all')
EDIT: skip_footer
was replaced with skipfooter
Result:
In [123]: df1
Out[123]:
a b c
0 78 68 33
1 62 26 30
2 99 35 13
3 73 97 4
4 85 7 53
5 80 20 95
6 40 52 96
7 36 23 76
8 96 73 37
9 39 35 24
In [124]: df2
Out[124]:
c1 c2 c3 c4
0 78 88 59 a
1 82 4 64 a
2 35 9 78 b
3 0 11 23 b
4 61 53 29 b
5 51 36 72 c
6 59 36 45 c
7 7 64 8 c
8 1 83 46 d
9 30 47 84 d