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MySQL - Rows to Columns
...temvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9 |
| 2 | C | 40 |
+--------+----------+-----------+
This will be our goal, the pretty pivot table:
select * from history_itemvalue_piv...
How to resize an image with OpenCV2.0 and Python2.6
I want to use OpenCV2.0 and Python2.6 to show resized images. I used and adopted this example but unfortunately, this code is for OpenCV2.1 and does not seem to be working on 2.0. Here my code:
...
Rename specific column(s) in pandas
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30
A much faster implementation would be to use list-comprehension if you need to rename a single c...
Odd behavior when Java converts int to byte?
...mber is the positive version of that number
For example: 11111111 goes to 00000001 = -1. This is what Java will display as the value.
What you probably want to do is know the unsigned value of the byte.
You can accomplish this with a bitmask that deletes everything but the least significant 8 bit...
Why `null >= 0 && null
...ncrements the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined .
...
How do you connect localhost in the Android emulator? [duplicate]
...
Use 10.0.2.2 to access your actual machine.
As you've learned, when you use the emulator, localhost (127.0.0.1) refers to the device's own loopback service, not the one on your machine as you may expect.
You can use 10.0.2.2 to ...
How do I get the time of day in javascript/Node.js?
...he getHours() method for the Date object.
getHours() return the time from 0 - 23, so make sure to deal with it accordingly. I think 0-23 is a bit more intuitive since military time runs from 0 - 23, but it's up to you.
With that in mind, the code would be something along the lines of:
var date = ...
How to change line width in ggplot?
... theme(axis.text.x = element_text(
colour = 'black', angle = 90, size = 13,
hjust = 0.5, vjust = 0.5),axis.title.x=element_blank()) +
ylab("FSI (%Change)") +
theme(axis.text.y = element_text(colour = 'black', size = 12),
axis.title.y = element_text(size = 12...
How to get unique values in an array
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120
Since I went on about it in the comments for @Rocket's answer, I may as well provide an example ...
When should I use Struct vs. OpenStruct?
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180
With an OpenStruct, you can arbitrarily create attributes. A Struct, on the other hand, must ha...