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Extracting specific columns in numpy array
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I assume you wanted columns 1 and 9?
To select multiple columns at once, use
X = data[:, [1, 9]]
To select one at a time, use
x, y = data[:, 1], data[:, 9]
With names:
data[:, ['Column Name1','Column Name2']]
You can get the names from data.dtype.names…
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Get selected option text with JavaScript
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Try options
function myNewFunction(sel) {
alert(sel.options[sel.selectedIndex].text);
}
<select id="box1" onChange="myNewFunction(this);">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option&g...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...
How do I fix the Visual Studio compile error, “mismatch between processor architecture”?
... item.
Find your project in the list, under Platform it will say "Any CPU"
Select the "Any CPU" option from the drop down and then select <New..>
From that dialog, select x86 from the "New Platform" drop down and make sure "Any CPU" is selected in the "Copy settings from" drop down.
Hit OK
You...
In PHP with PDO, how to check the final SQL parametrized query? [duplicate]
..... and finally EXECUTE ....
You won't be able to get some SQL string like SELECT * FROM ..., even if it would produce equivalent results, because no such query was ever actually sent to the database.
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String.Join method that ignores empty strings?
... simpler, since you can do it in SQL directly:
PostgreSQL & MySQL:
SELECT
concat_ws(' / '
, NULLIF(searchTerm1, '')
, NULLIF(searchTerm2, '')
, NULLIF(searchTerm3, '')
, NULLIF(searchTerm4, '')
) AS RPT_SearchTerms;
And even with the glorious MS-SQ...
SQL how to make null values come last when sorting ascending
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select MyDate
from MyTable
order by case when MyDate is null then 1 else 0 end, MyDate
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Invoke a callback at the end of a transition
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You want to listen for the "end" event of the transition.
// d3 v5
d3.select("#myid").transition().style("opacity","0").on("end", myCallback);
// old way
d3.select("#myid").transition().style("opacity","0").each("end", myCallback);
This demo uses the "end" event to chain many transitions in...
Delete all Duplicate Rows except for One in MySQL? [duplicate]
...te.
INSERT INTO tempTableName(cellId,attributeId,entityRowId,value)
SELECT DISTINCT cellId,attributeId,entityRowId,value
FROM tableName;
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SQL is null and = null [duplicate]
...e t (x int, y int);
insert into t values (null, null), (null, 1), (1, 1);
select 'x = null' as test , x, y from t where x = null
union all
select 'x != null', x, y from t where x != null
union all
select 'not (x = null)', x, y from t where not (x = null)
union all
select 'x = y', x, y from t where ...