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Is object empty? [duplicate]
...n-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length === 0) return true;
// If it isn't an object at this point
// it is empty, but it can't be anything *but* empty
// Is it empty? Depends on your application.
if (typeof...
Convert column classes in data.table
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105
For a single column:
dtnew <- dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘d...
How to check whether a pandas DataFrame is empty?
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505
You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print(...
How to write the Fibonacci Sequence?
...rning the Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 should = only those numbers between 1 & 20), I have written for the program to display all Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 displays = First 20 Fibonacci numbers). I thought I had a sure-fi...
How to remove convexity defects in a Sudoku square?
...Y = ImageMultiply[MorphologicalBinarize[GaussianFilter[srcAdjusted, 3, {2, 0}], {0.02, 0.05}], mask];
lX = ImageMultiply[MorphologicalBinarize[GaussianFilter[srcAdjusted, 3, {0, 2}], {0.02, 0.05}], mask];
I use connected component analysis again to extract the grid lines from these images. The g...
What to do about Eclipse's “No repository found containing: …” error messages?
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450
Quick answer
Go to Help → Install new software → Here uncheck “Contact all update sites d...
How to validate an email address in JavaScript
...^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
return re.test(String(email).toLowerCase());
}
Here's the example of regular expresion that accepts unicode:
const re = /^(([^<&...
“CASE” statement within “WHERE” clause in SQL Server 2008
...ery which contains "CASE" statement within "WHERE" clause. But SQL Server 2008 is giving some errors while executing it. Can anyone please help me with the correct query? Here is the query:
...
Python 3.x rounding behavior
I was just re-reading What’s New In Python 3.0 and it states:
11 Answers
11
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How to debug Lock wait timeout exceeded on MySQL?
...***
Type: InnoDB
Name:
Status:
=====================================
110514 19:44:14 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 4 seconds
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 9014315, signal count 780...