pandas: complex filter on rows of DataFrame

Posted by duckworthd on Stack Overflow See other posts from Stack Overflow or by duckworthd
Published on 2012-07-10T16:56:37Z Indexed on 2012/07/10 21:15 UTC
Read the original article Hit count: 300

Filed under:

pandas

I would like to filter rows by a function of each row, e.g.

def f(row):
  return sin(row['velocity'])/np.prod(['masses']) > 5

df = pandas.DataFrame(...)
filtered = df[apply_to_all_rows(df, f)]

Or for another more complex, contrived example,

def g(row):
  if row['col1'].method1() == 1:
    val = row['col1'].method2() / row['col1'].method3(row['col3'], row['col4'])
  else:
    val = row['col2'].method5(row['col6'])
  return np.sin(val)

df = pandas.DataFrame(...)
filtered = df[apply_to_all_rows(df, g)]

How can I do so?

Related posts about pandas

pandas: complex filter on rows of DataFrame

as seen on Stack Overflow - Search for 'Stack Overflow'
I would like to filter rows by a function of each row, e.g. def f(row): return sin(row['velocity'])/np.prod(['masses']) > 5 df = pandas.DataFrame(...) filtered = df[apply_to_all_rows(df, f)] Or for another more complex, contrived example, def g(row): if row['col1'].method1() == 1: … >>> More
How to sort a boxplot by the median values in pandas

as seen on Stack Overflow - Search for 'Stack Overflow'
I've got a dataframe outcome2 that I generate a grouped boxplot with in the following manner: In [11]: outcome2.boxplot(column='Hospital 30-Day Death (Mortality) Rates from Heart Attack',by='State') plt.ylabel('30 Day Death Rate') plt.title('30 Day Death Rate by State') Out [11]: What… >>> More
Creating a dataframe in pandas by multiplying two series together

as seen on Stack Overflow - Search for 'Stack Overflow'
Say I have two series in pandas, series A and series B. How do I create a dataframe in which all of those values are multiplied together, i.e. with series A down the left hand side and series B along the top. Basically the same concept as this, where series A would be the yellow on the left and series… >>> More
How split a column in two colunms in pandas

as seen on Stack Overflow - Search for 'Stack Overflow'
I have el next dataframe data=read_csv('enero.csv') data Fecha DirViento MagViento 0 2011/07/01 00:00 318 6.6 1 2011/07/01 00:15 342 5.5 2 2011/07/01 00:30 329 6.6 3 2011/07/01 00:45 279 … >>> More
How to find subgroups statistics in pandas?

as seen on Stack Overflow - Search for 'Stack Overflow'
I am grouping a DataFrame using multiple columns (e.g., columns A, B - my_df.groupby(['A','B']) ), is there a better (less lines of code, faster) way of finding how many rows are in each subgroup and how many subgroups are there in total? at the moment I am using: def get_grp_size(grp): grp['size']… >>> More

Developer IT

pandas: complex filter on rows of DataFrame - Developer IT

pandas: complex filter on rows of DataFrame

pandas

Related posts about pandas

pandas: complex filter on rows of DataFrame

How to sort a boxplot by the median values in pandas

Creating a dataframe in pandas by multiplying two series together

How split a column in two colunms in pandas

How to find subgroups statistics in pandas?

Categories cloud