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Change one value based on another value in pandas
... for you.
import pandas
df = pandas.read_csv("test.csv")
df.loc[df.ID == 103, 'FirstName'] = "Matt"
df.loc[df.ID == 103, 'LastName'] = "Jones"
As mentioned in the comments, you can also do the assignment to both columns in one shot:
df.loc[df.ID == 103, ['FirstName', 'LastName']] = 'Matt', 'Jone...
Is there a version of JavaScript's String.indexOf() that allows for regular expressions?
...
130
Combining a few of the approaches already mentioned (the indexOf is obviously rather simple), I ...
How does variable assignment work in JavaScript?
...
edited Aug 11 '18 at 14:50
Volker E.
5,1821111 gold badges4141 silver badges6262 bronze badges
answered...
What is a “context bound” in Scala?
...
107
Did you find this article? It covers the new context bound feature, within the context of arra...
Int division: Why is the result of 1/3 == 0?
...se returns the true result of division rounded towards zero. The result of 0.333... is thus rounded down to 0 here. (Note that the processor doesn't actually do any rounding, but you can think of it that way still.)
Also, note that if both operands (numbers) are given as floats; 3.0 and 1.0, or eve...
A better similarity ranking algorithm for variable length strings
...str1 varchar, str2 varchar)
RETURNS float8 AS '
str1.downcase!
pairs1 = (0..str1.length-2).collect {|i| str1[i,2]}.reject {
|pair| pair.include? " "}
str2.downcase!
pairs2 = (0..str2.length-2).collect {|i| str2[i,2]}.reject {
|pair| pair.include? " "}
union = pairs1.size + pairs2.size
inters...
Pretty printing XML with javascript
...;xsl:output indent="yes"/> instruction:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:template match="node()|@*">
<xsl:copy>
<xsl:apply-templates select="...
PHP Pass by reference in foreach [duplicate]
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edited Feb 10 '14 at 13:51
Boaz
17.1k88 gold badges5454 silver badges6262 bronze badges
an...
pandas read_csv and filter columns with usecols
...andas as pd
from StringIO import StringIO
csv = r"""dummy,date,loc,x
bar,20090101,a,1
bar,20090102,a,3
bar,20090103,a,5
bar,20090101,b,1
bar,20090102,b,3
bar,20090103,b,5"""
df = pd.read_csv(StringIO(csv),
header=0,
index_col=["date", "loc"],
usecols=["date", "loc", "x"],
...
How much size “Null” value takes in SQL Server
I have a large table with say 10 columns. 4 of them remains null most of the times. I have a query that does null value takes any size or no size in bytes. I read few articles some of them are saying :
...