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How can I loop through a List and grab each item?
...a foreach loop vs. a for loop. I just ran a quick test with your code with 100,000 entries in the List and the foreach loop took twice as long (actually 1.9 times as long). This isn't necessarily true in all situations, but in many. It depends on the size of the List, how many operations you do with...
What are the differences between type() and isinstance()?
...
+100
To summarize the contents of other (already good!) answers, isinstance caters for inheritance (an instance of a derived class is an ...
How are multi-dimensional arrays formatted in memory?
...converted to a pointer to the first element for most operators! sizeof(int[100]) != sizeof(int *) (unless you find a platform with 100 * sizeof(int) bytes/int, but that is a different thing.
– too honest for this site
Nov 18 '16 at 18:40
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Convert string in base64 to image and save on filesystem in Python
...py850808Au", line 8, in <module> image = Image.fromstring('RGB',(100,100),decodestring(imgData)) File "/opt/local/lib/python2.5/site-packages/PIL/Image.py", line 1744, in fromstring im.fromstring(data, decoder_name, args) File "/opt/local/lib/python2.5/site-packages/PIL/Image.py", ...
How to put an image in div with CSS?
...p;</div>
and put this into your css file:
div.picture1 {
width:100px; /*width of your image*/
height:100px; /*height of your image*/
background-image:url('yourimage.file');
margin:0; /* If you want no margin */
padding:0; /*if your want to padding */
}
otherwise, just use t...
How to get process ID of background process?
... number of background process as seen from jobs):
$ echo $$
3748
$ sleep 100 &
[1] 192
$ echo $!
192
$ kill %1
[1]+ Terminated sleep 100
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SCOPE_IDENTITY() for GUIDs?
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CREATE TABLE TestTable(KEY uniqueidentifier, ID VARCHAR(100), Name VARCHAR(100), Value tinyint);
Declare @id uniqueidentifier ;
DECLARE @TmpTable TABLE (KEY uniqueidentifier);
INSERT INTO [dbo].[TestTable]
([ID], [Name], Value])
OUTPUT INSERTED.KEY INTO @...
How to round a number to n decimal places in Java
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Assuming value is a double, you can do:
(double)Math.round(value * 100000d) / 100000d
That's for 5 digits precision. The number of zeros indicate the number of decimals.
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How do you find the row count for all your tables in Postgres
... @a_horse_with_no_name, by executing x_path function against a 100 million records.
– Spike
Apr 8 '19 at 10:24
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Why is MATLAB so fast in matrix multiplication?
...Update using R2018b on a WIN64 machine with 16 physical cores and a Tesla V100:
>> timeit(@()A*A)
ans =
0.0229
>> gputimeit(@()gA*gA)
ans =
4.8019e-04
(NB: at some point (I forget when exactly) gpuArray switched from MAGMA to cuBLAS - MAGMA is still used for some gpuArray opera...