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How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
...ns:
- Range.
E.g. a-z matches an lower case letters from a to z
E.g. 0-5 matches any number from 0 to 5
[] Match exactly one of the objects inside these brackets.
E.g. [a] matches the letter a
E.g. [abc] matches a single letter which can be a, b or c
E.g. [a-z] matches any single lower cas...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...
502
I would suggest using the duplicated method on the Pandas Index itself:
df3 = df3[~df3.index.du...
Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
How should I validate an e-mail address?
...am", as will org.apache.commons.validator.routines.EmailValidator)
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0...
How can I eliminate slow resolving/loading of localhost/virtualhost (a 2-3 second lag) on Mac OS X L
...environments on Mac OS X Lion (brand new macbook air purchased in January 2012), I have noticed that resolving to a virtual host is very slow (around 3 seconds) the first time but after that is fast as long as I continue loading it regularly.
...
Formatting floats without trailing zeros
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Me, I'd do ('%f' % x).rstrip('0').rstrip('.') -- guarantees fixed-point formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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640
Difference between == and ===
The difference between the loosely == equal operator and the stri...
Which is better, number(x) or parseFloat(x)?
... same:
parseFloat('3'); // => 3
Number('3'); // => 3
parseFloat('1.501'); // => 1.501
Number('1.501'); // => 1.501
parseFloat('1e10'); // => 10000000000
Number('1e10'); // => 10000000000
So as long as you have standard numeric input, there's no difference. However, if your input...
Pandas percentage of total with groupby
...swer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.randint(100000, 999999)
for _ in range(12...
What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?
... format: major.minor. This would result in:
[assembly: AssemblyVersion("1.0")]
If you're following SemVer strictly then this means you only update when the major changes, so 1.0, 2.0, 3.0, etc.
AssemblyFileVersion
Used for deployment. You can increase this number for every deployment. It is use...