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Calculate MD5 checksum for a file
...are the results afterwards is up to you; you can convert the byte array to base64 for example, or compare the bytes directly. (Just be aware that arrays don't override Equals. Using base64 is simpler to get right, but slightly less efficient if you're really only interested in comparing the hashes.)...
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 ...
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.
...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C
attached base packages:
[1] methods stats graphics grDevices utils datasets base
other attached packages:
[1] ggplot2_0.9.3.1
loaded via a namespace (and not attached):
[1] colorspace_1.2-4 dichromat_2.0-0 dig...
Convert integer to hexadecimal and back again
...the hex equivalent. HEX is not a terrible solution for this problem, but a base64 of the four bytes in the int would be even shorter (and you could trim the padding)
– James Hart
Aug 16 '11 at 21:08
...
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...
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
...
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) &...