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Can dplyr package be used for conditional mutating?
...), 2L,
ifelse(a %in% c(0,1,3,4) | c==4, 3L, NA_integer_)))
}
BASE_fun <- function(DF) { # R v3.1.0
transform(DF, g = ifelse(a %in% c(2,5,7) | (a==1 & b==4), 2L,
ifelse(a %in% c(0,1,3,4) | c==4, 3L, NA_integer_)))
}
system.time(ans1 <- DT_fun(DT))
# user s...
Setting the zoom level for a MKMapView
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Based on the fact that longitude lines are spaced apart equally at any point of the map, there is a very simple implementation to set the centerCoordinate and zoomLevel:
@interface MKMapView (ZoomLevel)
@property (assign, n...
Get the device width in javascript
... I'm not sure if this will work without the scaling set to 1:1 as a base ... var isMobile = window.matchMedia && window.matchMedia('(max-device-width: 960px)').matches || screen.width <= 960;
– Tracker1
Feb 27 '13 at 22:22
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Linq: adding conditions to the where clause conditionally
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}).ToList();
This will still only result in a single call to the database, which will be effectively just as efficient as writing the query in one pass.
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Java EE web development, where do I start and what skills do I need? [closed]
...n learn JPA at Jakarta EE tutorial part VIII. Also, EJB3 was much improved based on lessons learnt from Spring. See also When is it necessary or convenient to use Spring or EJB3 or all of them together?
Does Java have MVC? What about JSP? Can MVC and JSP be together? JavaBeans?
You can, but that'...
Entity Framework 4 / POCO - Where to start? [closed]
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His project structure looks just like an old nHibernate based project I was working on. Cept for all the WCF jazz, which I am keen on refreshing myself on. Solid link.
– Merritt
Aug 25 '10 at 20:18
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Interface Builder: What are the UIView's Layout iOS 6/7 Deltas for?
...the different styles, you can change the way Interface Builder presents it based on the OS it would be running on. This is contained within the File Inspector->Interface Builder Document (1st tab on the right bar), as so:
Does this exist if I like to code my interface by hand?
Not directly, b...
Undefined reference to `sin` [duplicate]
... external references. This library supports all of the
interfaces of the Base System, as defined in Volume 1, except for the
Math Routines.
Standard C Mathematical Library
This library supports
the Base System math routines, as defined in Volume 1. The cc option
-lm is used to se...
Minimum and maximum value of z-index?
I have a div in my HTML page. I am showing this div based on some condition, but the div is displaying behind the HTML element where I pointed the mouse cursor.
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Views vs Components in Ember.js
...your point. But I would think of a component as a black box, behaving only based on the data it gets passed in. And yes depending on what it does this could become a mess very quickly. A dedicated controller would make absolute sense, and a way it could work would be if components could become logic...