how to get formula result in excel using xlwings - python-2.7

What i want to do is 1)get a folmula result in excel and 2)update the values to the existing excel file. [ I created and wrote the folmula using "xlsxwriter". But when I tried openpyxl (or pandas) to retrieve the folmula result, it returns 0. I want to use "xlwings" to solve this problem, but no idea how to do it. can anyone help?
#openpyx
wb = openpyxl.load_workbook(filename=xlsx_name,data_only=True)
ws = wb.get_sheet_by_name("sheet1")
print "venn_value",(ws.cell('X2').value)
#pandas
fold_merge_data=pd.read_excel(xlsx_name,sheetname=1)
print fold_merge_data['Venn diagram'][:10]

Yes, xlwings can solve this problem for you because it uses pywin32 objects to interact with Excel, rather than just reading/writing xlsx or csv documents like openpyxl and pandas. This way, Excel actually executes the formula, and xlwings grabs the result.
In order to get the value you can do:
import xlwings as xw
sheet = xw.sheets.active # if the document is open
#otherwise use sheet = xw.Book(r'C:/path/to/file.xlsx').sheets['sheetname']
result = sheet['X2'].value
Also, note that you can set the formula using, for example
sheet['A1'].value = '=1+1' # or ='B1*2' if you want to reference other cells

import xlwings as xw
sheet = xw['Sheet1']
a2_formula = sheet.range('A2').formula
sheet.range('A2:A300').formula = a2_formula #it copys relative
You can use this method for copy formula or value

Related

Python - AttributeError: 'DataFrame' object has no attribute

I have a CSV file with various columns and everything worked perfectly for the past few months until I updated the file and got new information and now the one column does not appear to be picked up by Python. I am using Python 2.7 and have made sure I have the latest version of pandas.
When I downloaded the csv file from Yahoo Finance, I opened it in Excel and made changes to the format of the columns in order to make it more readable as all information was in one cell. I used the "Text to Column" feature and split up the data based on where the commas were.
Then I made sure that in each column there were no white spaces in the beginning of the cell using the Trim function in excel and left-aligning the data.
I tried the following and still get the same or similiar:
After the df = pd.read_csv("KIO.csv") I tried to read whether I can read the first few columns by using df.head() - but still got the same error.
I tried renaming the problematic column as suggested in a similiar post using:
df = df.rename(columns={"Close": "Closing"}) - here I got the same error again. "print df.columns" also led to the same issue.
"df[1]" - gave a long error with "KeyError: 1" at the end - I can print the entire thing if it it will assist.
Adding the "skipinitialspace=True" - no difference.
I thought the problem might be within the actual csv file information so I deleted all the columns and made my own information and I still got the same error.
Below is a portion of my code as the total code is very long:
enter code here
import pandas as pd
import matplotlib.pyplot as plt
import matplotlib.dates as pltdate
import datetime
import matplotlib.animation as animation
import numpy as np
df = pd.read_csv("KIO.csv", skipinitialspace=True)
#df.head()
#Close = df.columns[0]
#df= df.rename(columns={"Close": "Closing"})
df1 = pd.read_csv("USD-ZAR.csv")
kio_close = pd.DataFrame(df.Close)
exchange = pd.DataFrame(df1.Value)
dates = df["Date"]
dates1 = df1["Date"]
The above variables have been used throughout the remaining code though so if this issue can be solved here the remaining code will be right.
This is copy/paste of the error:
Blockquote
Traceback (most recent call last):
File "C:/Users/User/Documents/PycharmProjects/Trading_GUI/GUI_testing.py", line 33, in
kio_close = pd.DataFrame(df.Close)
File "C:\Python27\lib\site-packages\pandas\core\generic.py", line 4372, in getattr
return object.getattribute(self, name)
AttributeError: 'DataFrame' object has no attribute 'Close'
Thank you so much in advance.
#Rip_027 This is in regards to your last comment. I used to have the same issue whenever I open a csv file by simply double clicking the file icon. You need to launch Excel first, then get external data. Link below has more details,which will serve as a guideline. Hope this helps.
https://www.hesa.ac.uk/support/user-guides/import-csv

How can I save histogram plot in python?

I have following code that generates a histogram. How can I save the histogram automatically using the code? I tried what we do for other plot types but that did not work for histogram.a is a 'numpy.ndarray'.
a = [-0.86906864 -0.72122614 -0.18074998 -0.57190212 -0.25689268 -1.
0.68713553 0.29597819 0.45022949 0.37550592 0.86906864 0.17437203
0.48704826 0.2235648 0.72122614 0.14387731 0.94194514 ]
fig = pl.hist(a,normed=0)
pl.title('Mean')
pl.xlabel("value")
pl.ylabel("Frequency")
pl.savefig("abc.png")
This works for me:
import matplotlib.pyplot as pl
import numpy as np
a = np.array([-0.86906864, -0.72122614, -0.18074998, -0.57190212, -0.25689268 ,-1. ,0.68713553 ,0.29597819, 0.45022949, 0.37550592, 0.86906864, 0.17437203, 0.48704826, 0.2235648, 0.72122614, 0.14387731, 0.94194514])
fig = pl.hist(a,normed=0)
pl.title('Mean')
pl.xlabel("value")
pl.ylabel("Frequency")
pl.savefig("abc.png")
a in the OP is not a numpy array and its format also needs to be modified (it needs commas, not spaces as delimiters). This program successfully saves the histogram in the working directory. If it still does not work, supply it with a full path to the location where you want to save it like this
pl.savefig("/Users/atru/abc.png")
The pl.show() statement should not be placed before savefig() as it creates a new figure which makes savefig() save a blank figure instead of the desired one as explained in this post.

Changing column width from excel files

I have a file like so that I am reading from excel:
Year Month Day
1 2 1
2 1 2
I want to specify the column width that excel recognizes. I would like to do it in pandas but I don't see a option. I have tried to do it with the module StyleFrame.
This is my code:
from StyleFrame import StyleFrame
import pandas as pd
df=pd.read_excel(r'P:\File.xlsx')
excel_writer = StyleFrame.ExcelWriter(r'P:\File.xlsx')
sf=StyleFrame(df)
sf=sf.set_column_width(columns=['Year', 'Month'], width=4.0)
sf=sf.set_column_width(columns=['Day'], width=6.00)
sf=sf.to_excel(excel_writer=excel_writer)
excel_writer.save()
but the formatting isn't saved when I open the new file.
Is there a way to do it in pandas? I would even take a pure python solution to this, pretty much anything that works.
As for your question on how to remove the headers, you can simply pass header=False to to_excel:
sf.to_excel(excel_writer=excel_writer, header=False).
Note that this will still result with the first line of the table being bold.
If you don't want that behavior you can update to 0.1.6 that I just released.

Python/Pandas: How do I convert from datetime64[ns] to datetime

I have a script that processes an Excel file. The department that sends it has a system that generated it, and my script stopped working.
I suddenly got the error Can only use .str accessor with string values, which use np.object_ dtype in pandas for the following line of code:
df['DATE'] = df['Date'].str.replace(r'[^a-zA-Z0-9\._/-]', '')
I checked the type of the date columns in the file from the old system (dtype: object) vs the file from the new system (dtype: datetime64[ns]).
How do I change the date format to something my script will understand?
I saw this answer but my knowledge about date formats isn't this granular.
You can use apply function on the dataframe column to convert the necessary column to String. For example:
df['DATE'] = df['Date'].apply(lambda x: x.strftime('%Y-%m-%d'))
Make sure to import datetime module.
apply() will take each cell at a time for evaluation and apply the formatting as specified in the lambda function.
pd.to_datetime returns a Series of datetime64 dtype, as described here:
https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.to_datetime.html
df['DATE'] = df['Date'].dt.date
or this:
df['Date'].map(datetime.datetime.date)
You can use pd.to_datetime
df['DATE'] = pd.to_datetime(df['DATE'])

How would I format data in a PrettyTable?

I'm getting the text from the title and href attributes from the HTML. The code runs fine and I'm able to import it all into a PrettyTable fine. The problem that I face now is that there are some titles that I believe are too large for one of the boxes in the table and thus distort the entire PrettyTable made. I've tried adjusting the hrules, vrules, and padding_width and have not found a resolution.
from bs4 import BeautifulSoup
from prettytable import PrettyTable
import urllib
r = urllib.urlopen('http://www.genome.jp/kegg-bin/show_pathway?map=hsa05215&show_description=show').read()
soup = BeautifulSoup((r), "lxml")
links = [area['href'] for area in soup.find_all('area', href=True)]
titles = [area['title'] for area in soup.find_all('area', title=True)]
k = PrettyTable()
k.field_names = ["ID", "Active Compound", "Link"]
c = 1
for i in range(len(titles)):
k.add_row([c, titles[i], links[i]])
c += 1
print(k)
How I would like the entire table to display as:
print (k.get_string(start=0, end=25))
If PrettyTable can't do it. Are there any other recommended modules that could accomplish this?
This was not a formatting error, but rather the overall size of the table created was so large that the python window could not accommodate all the values on the screen.
This proven by changing to a much smaller font size. If it helps anyone exporting as .csv then arranging in Excel helped.