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How do I get the row count of a pandas DataFrame?
...eturn non-NaN counts for each column:
df.count()
A 5
B 3
dtype: int64
For Series, use Series.count to similar effect:
s.count()
# 3
Group-wise Row Count: GroupBy.size
For DataFrames, use DataFrameGroupBy.size to count the number of rows per group.
df.groupby('A').size()
A
a 2
b ...
Lombok is not generating getter and setter
I just tried to send a Maven-based project to another computer and HORROR,
red markers everywhere!!
20 Answers
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Java equivalent of unsigned long long?
In C++, I enjoyed having access to a 64 bit unsigned integer, via unsigned long long int , or via uint64_t . Now, in Java longs are 64 bits, I know. However, they are signed.
...
Can't open config file: /usr/local/ssl/openssl.cnf on Windows [duplicate]
I have installed OpenSSL 64. I want to use a certificate for my nodejs https server. I ran the following command:
7 Answers...
Why does installing Nokogiri on Mac OS fail with libiconv is missing?
...or unsupported file format which is not the architecture being linked (x86_64) for architecture x86_64
Uhh, what? After a lot of googling, I came across this miracle post: http://www.refresherate.com/2010/01/08/fixing-ld-warning-in-usrlocalliblibz-dylib-file-is-not-of-required-architecture/
Appar...
Detect application heap size in Android
... to 32:
maxMemory: 33554432
getMemoryClass: 32
With VM Heap Size set to 64:
maxMemory: 67108864
getMemoryClass: 32
In addition to the above, I tested on a Novo7 Paladin tablet running Ice Cream Sandwich.
This was essentially a stock version of ICS, except that I've rooted the tablet through...
How do I make a textbox that only accepts numbers?
...
protected override void OnKeyPress(KeyPressEventArgs e)
{
base.OnKeyPress(e);
NumberFormatInfo fi = CultureInfo.CurrentCulture.NumberFormat;
string c = e.KeyChar.ToString();
if (char.IsDigit(c, 0))
return;
if ((SelectionStart == 0) &...
dropping infinite values from dataframes in pandas?
...
Use (fast and simple):
df = df[np.isfinite(df).all(1)]
This answer is based on DougR's answer in an other question.
Here an example code:
import pandas as pd
import numpy as np
df=pd.DataFrame([1,2,3,np.nan,4,np.inf,5,-np.inf,6])
print('Input:\n',df,sep='')
df = df[np.isfinite(df).all(1)]
prin...
What is the MySQL VARCHAR max size?
...
As per the online docs, there is a 64K row limit and you can work out the row size by using:
row length = 1
+ (sum of column lengths)
+ (number of NULL columns + delete_flag + 7)/8
+ (number of variable-length columns)
...
Storing SHA1 hash values in MySQL
...ch occured when I wanted to store the result of a SHA1 hash in a MySQL database:
7 Answers
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