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Does java.util.List.isEmpty() check if the list itself is null? [duplicate]
...I deleted my stupid comment, before I saw your answer. Maybe he comes from PHP where we have !empty($foo) as somewhat an alias for isset($foo) && $foo != "".
– Aufziehvogel
Jul 16 '12 at 20:39
...
How to get all files under a specific directory in MATLAB?
...irData = dir(dirName); %# Get the data for the current directory
dirIndex = [dirData.isdir]; %# Find the index for directories
fileList = {dirData(~dirIndex).name}'; %'# Get a list of the files
if ~isempty(fileList)
fileList = cellfun(@(x) fullfile(dirName,x),... %# Prepend path to...
Filtering a data frame by values in a column [duplicate]
...
The subset command is not necessary. Just use data frame indexing
studentdata[studentdata$Drink == 'water',]
Read the warning from ?subset
This is a convenience function intended for use interactively. For
programming it is better to use the standard subsetting functions ...
How to revert multiple git commits?
...ght mean checkout branch foo (switch to branch) or checkout file foo (from index). -- is used to disambiguate, e.g. git checkout -- foo is always about file.
– Jakub Narębski
Jan 23 '13 at 2:34
...
Fastest way to count exact number of rows in a very large table?
...db_partition_stats st
WHERE
object_name(object_id) = 'MyBigtable' AND (index_id < 2)
2 runs, both under 1 second, count = 1,401,659,670
The second one has less rows = wrong. Would be the same or more depending on writes (deletes are done out of hours here)
...
How to add a new row to datagridview programmatically
...s you did: row.Cells["Column2"].Value = "XYZ"; ... You have to look up the index first: row.Cells[yourDataGridView.Columns["Column2"].Index].Value = "XYZ";
– Tizz
Dec 3 '12 at 19:55
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Accessing @attribute from SimpleXML
...ode. You can then var_dump the return value of the function.
More info at php.net
http://php.net/simplexmlelement.attributes
Example code from that page:
$xml = simplexml_load_string($string);
foreach($xml->foo[0]->attributes() as $a => $b) {
echo $a,'="',$b,"\"\n";
}
...
Comparing two files in linux terminal
...u prefer the diff output style from git diff, you can use it with the --no-index flag to compare files not in a git repository:
git diff --no-index a.txt b.txt
Using a couple of files with around 200k file name strings in each, I benchmarked (with the built-in timecommand) this approach vs some o...
How do you rotate a two dimensional array?
...imensional array:
matrix = [
[0,1],
[2,3]
]
Therefore the first index position accesses the row. The second index position accesses the column:
matrix[row][column]
We’ll define a utility function to print a matrix.
def print_matrix(matrix):
for row in matrix:
print row
...
How to generate a random string of a fixed length in Go?
...s is a string constant.)
And at what cost? Nothing at all. strings can be indexed which indexes its bytes, perfect, exactly what we want.
Our next destination looks like this:
const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
func RandStringBytes(n int) string {
b :=...