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GroupBy pandas DataFrame and select most common value
...ata frame with three string columns. I know that the only one value in the 3rd column is valid for every combination of the first two. To clean the data I have to group by data frame by first two columns and select most common value of the third column for each combination.
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Error type 3 Error: Activity class {} does not exist
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Is there a list of screen resolutions for all Android based phones and tablets? [closed]
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130
(out of date) Spreadsheet of device metrics.
SEE ALSO:
Device Metrics - Material Design.
Scree...
Leading zeros for Int in Swift
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703
Assuming you want a field length of 2 with leading zeros you'd do this:
import Foundation
for ...
How to find out what type of a Mat object is with Mat::type() in OpenCV
...e CV_16U: r = "16U"; break;
case CV_16S: r = "16S"; break;
case CV_32S: r = "32S"; break;
case CV_32F: r = "32F"; break;
case CV_64F: r = "64F"; break;
default: r = "User"; break;
}
r += "C";
r += (chans+'0');
return r;
}
If M is a var of type Mat you can call it ...
Extracting the last n characters from a ruby string
...a one liner, you can put a number greater than the size of the string:
"123".split(//).last(5).to_s
For ruby 1.9+
"123".split(//).last(5).join("").to_s
For ruby 2.0+, join returns a string
"123".split(//).last(5).join
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Ways to save enums in database
...me :
public enum Suit {
Unknown = 4,
Heart = 1,
Club = 3,
Diamond = 2,
Spade = 0 }
in order to maintain the legacy numerical values stored in the database.
How to sort them in the database
The question comes up: lets say i wanted to order the values. Some people m...
Base64: What is the worst possible increase in space usage?
...the size of the base-64 representation of a string of size n is:
ceil(n / 3) * 4
So, for a 16kB array, the base-64 representation will be ceil(16*1024/3)*4 = 21848 bytes long ~= 21.8kB.
A rough approximation would be that the size of the data is increased to 4/3 of the original.
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