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What does “zend_mm_heap corrupted” mean
...on that I've never had before. I decided to check the Apache's error log, and I found an error message saying "zend_mm_heap corrupted". What does this mean.
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How can I apply a function to every row/column of a matrix in MATLAB?
...
Many built-in operations like sum and prod are already able to operate across rows or columns, so you may be able to refactor the function you are applying to take advantage of this.
If that's not a viable option, one way to do it is to collect the rows or c...
How to change max_allowed_packet size
...on in your file:
max_allowed_packet=500M
then restart the MySQL service and you are done.
See the documentation for further information.
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Why does ~True result in -2?
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int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 Flip all the bits, add 1 to the resulting number and interpret the result as a binary representation of the magnitude and add a negative sign (since the number begins...
Moving decimal places over in a double
...Decimal.
The problem you have is that 0.1 is not an exact representation, and by performing the calculation twice, you are compounding that error.
However, 100 can be represented accurately, so try:
double x = 1234;
x /= 100;
System.out.println(x);
which prints:
12.34
This works because Doub...
Access denied for user 'root@localhost' (using password:NO)
I'm new to MySQL, I'm trying to run WordPress in my Windows desktop and it needs MySQL.
16 Answers
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Get local IP address in node.js
I have a simple node.js program running on my machine and I want to get local IP address of PC on which my program is running. How do I get it with node.js?
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How to set Sqlite3 to be case insensitive when string comparing?
...ocase in the column definition (the other options are binary (the default) and rtrim; see here). You can specify collate nocase when you create an index as well. For example:
create table Test
(
Text_Value text collate nocase
);
insert into Test values ('A');
insert into Test values ('b');
i...
Remove duplicated rows using dplyr
...mple(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data frame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need...
Java packages com and org
What are the meaning of the packages org and com in Java?
4 Answers
4
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