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Guards vs. if-then-else vs. cases in Haskell
...and guards should almost always be used instead.
let absOfN =
if n < 0 -- Single binary expression
then -n
else n
Every if..then..else expression can be replaced by a guard if it is at the top level of a function, and this should generally be preferred, since you can add more cases more...
Showing data values on stacked bar chart in ggplot2
...
From ggplot 2.2.0 labels can easily be stacked by using position = position_stack(vjust = 0.5) in geom_text.
ggplot(Data, aes(x = Year, y = Frequency, fill = Category, label = Frequency)) +
geom_bar(stat = "identity") +
geom_text(size =...
Pip freeze vs. pip list
...ecific format for pip to understand, which is
feedparser==5.1.3
wsgiref==0.1.2
django==1.4.2
...
That is the "requirements format".
Here, django==1.4.2 implies install django version 1.4.2 (even though the latest is 1.6.x).
If you do not specify ==1.4.2, the latest version available would be in...
inserting characters at the start and end of a string
...
answered Apr 8 '12 at 0:47
Mark ByersMark Byers
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...
How to force LINQ Sum() to return 0 while source collection is empty
...uery throws an exception. In that case I'd prefer to have the sum equalize 0 rather than an exception being thrown.
Would this be possible in the query itself - I mean rather than storing the query and checking query.Any() ?
...
How do I break out of a loop in Scala?
...f loops.
Suppose you want to sum numbers until the total is greater than 1000. You try
var sum = 0
for (i <- 0 to 1000) sum += i
except you want to stop when (sum > 1000).
What to do? There are several options.
(1a) Use some construct that includes a conditional that you test.
var sum...
How are cookies passed in the HTTP protocol?
...
302
The server sends the following in its response header to set a cookie field.
Set-Cookie:name=v...
How to change column datatype from character to numeric in PostgreSQL 8.4
...nding on your data):
alter table presales alter column code type numeric(10,0) using code::numeric;
-- Or if you prefer standard casting...
alter table presales alter column code type numeric(10,0) using cast(code as numeric);
This will fail if you have anything in code that cannot be cast to num...
Use jQuery to get the file input's selected filename without the path
... |
edited Jun 16 '11 at 0:37
answered Jun 16 '11 at 0:21
...
outline on only one border
... see your image, here's how to achieve it.
.element {
padding: 5px 0;
background: #CCC;
}
.element:before {
content: "\a0";
display: block;
padding: 2px 0;
line-height: 1px;
border-top: 1px dashed #000;
}
.element p {
padding: 0 10px;
}
<div class="element">...