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Factors in R: more than an annoyance?
...ls(x)
levels(x$Species)
# [1] "setosa"
This is how to keep levels you've selected out from getting in ggplot legends.
Internally, factors are integers with an attribute level character vector (see attributes(iris$Species) and class(attributes(iris$Species)$levels)), which is clean. If you had to ...
Prevent form submission on Enter key press
I have a form with two text boxes, one select drop down and one radio button . When the enter key is pressed, I want to call my JavaScript function, but when I press it, the form is submitted.
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Scala how can I count the number of occurrences in a list
...wer (vs comment); i would love to enthusiastically upvote, if it were (and select it as the best answer if i were the OP);
– doug
Feb 13 '15 at 4:01
1
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Storing JSON in database vs. having a new column for each key
..._food pizza
.................
and query via something like this:
select meta_val from `table` where meta_key = 'name' and uid = 1 order by meta_id desc
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Gradle - getting the latest release version of a dependency
... + for the version, and want to know which version is actually being used, select Project in the sidebar, and then under External Libraries you will see the actual version number in use.
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First letter capitalization for EditText
...d a new item, I have a Dialog with an EditText view showing inside. When I select the EditText view, the keyboard comes up to enter text, as it should. In most applications, the default seems to be that the shift key is held for the first letter... although it does not do this for my view. There has...
REST API 404: Bad URI, or Missing Resource?
...s no data which align to the query conditions (for example zero record was selected).
When there was no data to sent back to the client I prepared an perfect JSON message with internal error code, etc. to inform the client about the reason of the "Not Found" and it was sent back to the client with ...
Xcode: What is a target and scheme in plain language?
...between running your app and your unit tests without needing to toggle the selected target.
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Create Django model or update if exists
...large collection it won't scale well. update_or_create always first runs a SELECT and thereafter an UPDATE.
for the_bar in bars:
updated_rows = SomeModel.objects.filter(bar=the_bar).update(foo=100)
if not updated_rows:
# if not exists, create new
SomeModel.object...
What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
...ow demonstrate the noticeable artifacting of lossy compression algorithms; select the thumbnail image to view the full size version.
Each format is different as described below:
JPEG
JPEG (Joint Photographic Experts Group) files are (in most cases) a lossy format; the DOS filename extension is JPG...