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When to use symbols instead of strings in Ruby?
...eference the symbol, saving memory. So every time the interpreter reads :my_key it can take it from memory instead of instantiate it again. This is less expensive than initializing a new string every time.
You can get a list all symbols that are already instantiated with the command Symbol.all_sym...
Saving interactive Matplotlib figures
...can even extract the data from the plots:
data = figx.axes[0].lines[0].get_data()
(It works for lines, pcolor & imshow - pcolormesh works with some tricks to reconstruct the flattened data.)
I got the excellent tip from Saving Matplotlib Figures Using Pickle.
...
Eclipse hangs on loading workbench
...
#
#
# error
#
# show an error message and exit
#
# params:
# 1: l_msg - the message to display
error() {
local l_msg="$1"
echo "error: $l_msg" 1>&2
exit 1
}
#
# autoinstall
#
# check that l_prog is available by calling which
# if not available install from given package de...
C# HttpClient 4.5 multipart/form-data upload
... string url = "myAddress/myWS/api/Home/SendImage?foto="; await _client.PostAsync(url, requestContent); return "ok"; }
– atapi19
Jan 29 '18 at 14:59
...
Python timedelta in years
...
from dateutil.relativedelta import relativedelta
def yearsago(years, from_date=None):
if from_date is None:
from_date = datetime.now()
return from_date - relativedelta(years=years)
If you'd rather stick with the standard library, the answer is a little more complex::
from dateti...
Can I use a min-height for table, tr or td?
...e width="100%" cellspacing="0" class="htmlgrid-table">
<tr id="tr_0">
<td width="3%" align="center" class="readOnlyCell rowNumberColumn">1</td>
<td align="left" width="40%" id="td_0_0" class="readOnlyCell gContentSection">411978430-Intimate:Ruby...
FileSystemWatcher Changed event is raised twice
...e "fixed" that problem using the following strategy in my delegate:
// fsw_ is the FileSystemWatcher instance used by my application.
private void OnDirectoryChanged(...)
{
try
{
fsw_.EnableRaisingEvents = false;
/* do my stuff once asynchronously */
}
finally
{
...
When should I use C++14 automatic return type deduction?
...he reason it's int* is because that's what std::vector<int>::iterator_type is with your current build options!
– Steve Jessop
Apr 13 '18 at 12:16
...
What does “The APR based Apache Tomcat Native library was not found” mean?
...
On RHEL Linux just issue:
yum install tomcat-native.x86_64
/Note:depending on Your architecture 64bit or 32bit package may have different extension/
That is all. After that You will find in the log file next informational message:
INFO: APR capabilities: IPv6 [true], sendfile...
Create unique constraint with null columns
...
Create two partial indexes:
CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id)
WHERE menu_id IS NOT NULL;
CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id)
WHERE menu_id IS NULL;
This way, there can only be one combination...