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Append a NumPy array to a NumPy array
...p
In [2]: a = np.array([[1, 2, 3], [4, 5, 6]])
In [3]: b = np.array([[9, 8, 7], [6, 5, 4]])
In [4]: np.concatenate((a, b))
Out[4]:
array([[1, 2, 3],
[4, 5, 6],
[9, 8, 7],
[6, 5, 4]])
or this:
In [1]: a = np.array([1, 2, 3])
In [2]: b = np.array([4, 5, 6])
In [3]: np.vst...
warning: implicit declaration of function
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@Flimm, C99 and C89/C90 has different setting for this
– How Chen
Jan 15 '15 at 6:06
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Java FileOutputStream Create File if not exists
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Damiano
87422 gold badges1010 silver badges2222 bronze badges
answered Mar 8 '12 at 16:00
talnicolastalnicola...
How do I ALTER a PostgreSQL table and make a column unique?
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278
I figured it out from the PostgreSQL docs, the exact syntax is:
ALTER TABLE the_table ADD CONST...
Order discrete x scale by frequency/value
...different than:
# mtcars$cyl2 <- factor(mtcars$cyl, levels = c("6","4","8"))
# You can manually set the levels in whatever order you please.
ggplot(mtcars, aes(cyl2)) + geom_bar()
As James pointed out in his answer, reorder is the idiomatic way of reordering factor levels.
mtcars$cyl3 <-...
MySQL: What's the difference between float and double?
...get rounded and decimals do not. Decimal(9,3) could be for example 123456.789 whereas if you tried to store 123456.789 it would get inserted as 123456.0 as a float.
– Blake
Mar 6 '18 at 20:18
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phpinfo() - is there an easy way for seeing it?
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edited Jan 14 '19 at 15:18
answered Aug 25 '11 at 12:34
Ja...
How can I change the default Django date template format?
I have dates in ISO 8601 format in the database, %Y-%m-%d . However, when the date is passed on to the template, it comes out as something like Oct. 16, 2011 .
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how to append a list object to another
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dmeister
30.8k1818 gold badges6666 silver badges9191 bronze badges
answered Sep 19 '09 at 22:52
UncleBensUncleBen...