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Converting a column within pandas dataframe from int to string
I have a dataframe in pandas with mixed int and str data columns. I want to concatenate first the columns within the dataframe. To do that I have to convert an int column to str .
I've tried to do as follows:
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Why would you use Expression rather than Func?
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When you want to treat lambda expressions as expression trees and look inside them instead of executing them. For example, LINQ to SQL gets the expression and converts it to the equivalent SQL statement and submits it to server (rather than executing the lambda).
Conceptually, Expression<Fun...
How to implement has_many :through relationships with Mongoid and mongodb?
Using this modified example from the Rails guides , how does one model a relational "has_many :through" association using mongoid?
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Automatically start a Windows Service on install
I have a Windows Service which I install using the InstallUtil.exe. Even though I have set the Startup Method to Automatic, the service does not start when installed, I have to manually open the services and click start. Is there a way to start it either via the command line, or through the code of ...
Generate a random number in the range 1 - 10
Since my approach for a test query which I worked on in this question did not work out, I'm trying something else now. Is there a way to tell pg's random() function to get me only numbers between 1 and 10?
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What does the PHP error message “Notice: Use of undefined constant” mean?
PHP is writing this error in the logs: "Notice: Use of undefined constant".
9 Answers
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Override Python's 'in' operator?
If I am creating my own class in Python, what function should I define so as to allow the use of the 'in' operator, e.g.
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Correct way to write line to file?
I'm used to doing print >>f, "hi there"
14 Answers
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Does C have a “foreach” loop construct?
Almost all languages have a foreach loop or something similar. Does C have one? Can you post some example code?
12 Answer...
Pass request headers in a jQuery AJAX GET call
I am trying to pass request headers in an AJAX GET using jQuery. In the following block, "data" automatically passes the values in the querystring. Is there a way to pass that data in the request header instead ?
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