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Boolean Field in Oracle
...as JDBC, OCCI, and other programming environments,
it's better to select 0 for false and 1 for true so it can work
correctly with the getBoolean and setBoolean functions.
Basically they advocate method number 2, for efficiency's sake, using
values of 0/1 (because of interoperability with JD...
How to add a new row to an empty numpy array
...
The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty array but it has the proper dimensionality.
>>> arr
array([], shape=(0, 3), dtype=int64)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr =...
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...
What is a regular expression for a MAC Address?
...
The standard (IEEE 802) format for
printing MAC-48 addresses in
human-friendly form is six groups of
two hexadecimal digits, separated by
hyphens - or colons :.
So:
^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$
...
How can I force division to be floating point? Division keeps rounding down to 0?
... I want to calculate a / b , so if I use integer division I'll always get 0 with a remainder of a .
11 Answers
...
NPM - How to fix “No readme data”
... file... :/
– mgol
Feb 3 '14 at 15:20
3
I too have a README.md file with a whole bunch of stuff i...
How do I measure execution time of a command on the Windows command line?
...
30 Answers
30
Active
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Removing trailing newline character from fgets() input
... ugly way:
char *pos;
if ((pos=strchr(Name, '\n')) != NULL)
*pos = '\0';
else
/* input too long for buffer, flag error */
The slightly strange way:
strtok(Name, "\n");
Note that the strtok function doesn't work as expected if the user enters an empty string (i.e. presses only Enter). ...
How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
17
...
Context switches much slower in new linux kernels
We are looking to upgrade the OS on our servers from Ubuntu 10.04 LTS to Ubuntu 12.04 LTS. Unfortunately, it seems that the latency to run a thread that has become runnable has significantly increased from the 2.6 kernel to the 3.2 kernel. In fact the latency numbers we are getting are hard to belie...