In xlswriter, once a format is defined, how can you apply it to a range and not to the whole column or the whole row? for example: this gets applied it to the whole “B” column, but how can this “perc_fmt” applied to a range, for example, if I do: it says: Answer Actually I found a work…
Tag: pandas
Groupby and lag all columns of a dataframe?
I want to lag every column in a dataframe, by group. I have a frame like this: which looks like and I want it to look like this: This question manages the result for a single column, but I have an arbitrary number of columns, and I want to lag all of them. I can use groupby and apply, but
Write Large Pandas DataFrames to SQL Server database
I have 74 relatively large Pandas DataFrames (About 34,600 rows and 8 columns) that I am trying to insert into a SQL Server database as quickly as possible. After doing some research, I learned that the good ole pandas.to_sql function is not good for such large inserts into a SQL Server database, which was th…
How to read a Parquet file into Pandas DataFrame?
How to read a modestly sized Parquet data-set into an in-memory Pandas DataFrame without setting up a cluster computing infrastructure such as Hadoop or Spark? This is only a moderate amount of data that I would like to read in-memory with a simple Python script on a laptop. The data does not reside on HDFS. …
Python: Pandas Dataframe how to multiply entire column with a scalar
How do I multiply each element of a given column of my dataframe with a scalar? (I have tried looking on SO, but cannot seem to find the right solution) Doing something like: gives me a warning: Note: If possible, I do not want to be iterating over the dataframe and do something like this…as I think any…
Python – Command “python setup.py egg_info” failed with error code 1 in /tmp/pip-build-21ft0H/pandas
I’m using Centos 7 and Python 2.7.5. The problem is when I install Pandas, i got this error message I already tried a lot of solutions but no success even yum -y update. Can’t install via pip because of egg_info error Python pip install fails: invalid command egg_info https://www.digitalocean.com/…
Pandas dataframe from nested dictionary
My dictionary looks like this: I want to get a dataframe that looks like this: I tried calling pandas.from_dict(), but it did not give me the desired result. So, what is the most elegant, practical way to achieve this? EDIT: In reality, my dictionary is of depth 4, so I’d like to see a solution for that…
How to convert datetime object to milliseconds
I am parsing datetime values as follows: How can I convert this datetime objects to milliseconds? I didn’t see mention of milliseconds in the doc of to_datetime. Update (Based on feedback): This is the current version of the code that provides error TypeError: Cannot convert input to Timestamp. The colu…
How to remove string value from column in pandas dataframe
I am trying to write some code that splits a string in a dataframe column at comma (so it becomes a list) and removes a certain string from that list if it is present. after removing the unwanted string I want to join the list elements again at comma. My dataframe looks like this: So basically my goal is to
AttributeError: Can only use .dt accessor with datetimelike values
Hi I am using pandas to convert a column to month. When I read my data they are objects: So I am first making them to date time and then try to make them as months: Also if that helps: So, the error I get is like this: EDITED: Date columns are like this: Do you have any ideas? Thank