大约有 34,100 项符合查询结果（耗时：0.0295秒） [XML]
Ruby on Rails: how do I sort with two columns using ActiveRecord?
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edited Aug 27 '10 at 20:28
answered Aug 27 '10 at 20:22
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How can I create a correlation matrix in R?
... between your matrix x and matrix y. Ex.:
set.seed(1)
x <- matrix(rnorm(20), nrow=5, ncol=4)
y <- matrix(rnorm(15), nrow=5, ncol=3)
COR <- cor(x,y)
COR
image(x=seq(dim(x)[2]), y=seq(dim(y)[2]), z=COR, xlab="x column", ylab="y column")
text(expand.grid(x=seq(dim(x)[2]), y=seq(dim(y)[2])), la...
How to get english language word database? [closed]
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edited Jul 27 '15 at 20:53
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answered Feb 6 '10 at 15:35
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How to use mongoimport to import csv
...records. I had saved my file that didn't work using the OSX Excel for Mac 2011 version using the default "Save as.." "xls as csv" without specifying "Windows Comma Separated(.csv)" format specifically. After researching this site and trying the "Save As again using "Windows Comma Separated (.csv)"...
How to revert uncommitted changes including files and folders?
...ge --abort.
– htanata
Oct 12 '16 at 20:46
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show 1 more comment
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Password reset for Azure database
... first.
– jakejgordon
Oct 25 '15 at 20:00
I couldn't remember my username and couldn't find it listed anywhere so I de...
Google Map API V3: How to add Custom data to markers
...w google.maps.Marker({
map: map,
position: new google.maps.LatLng(-20, 0)
});
markerC['customInfo'] = "Marker C";
Then to retrieve it in a similar manner:
google.maps.event.addListener(markerA, 'click', function() {
alert(this.customInfo);
});
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Calculate difference between two datetimes in MySQL
...F MySQL function. For example, you can use:
SELECT TIMESTAMPDIFF(SECOND, '2012-06-06 13:13:55', '2012-06-06 15:20:18')
In your case, the third parameter of TIMSTAMPDIFF function would be the current login time (NOW()). Second parameter would be the last login time, which is already in the databas...
Ignore invalid self-signed ssl certificate in node.js with https.request?
...ain application js.
– Xedecimal
Sep 20 '14 at 0:33
This also worked for NodeJS & SailJS combo. I added it at the t...
Selecting with complex criteria from pandas.DataFrame
... B C
0 9 40 300
1 9 70 700
2 5 70 900
3 8 80 900
4 7 50 200
5 9 30 900
6 2 80 700
7 2 80 400
8 5 80 300
9 7 70 800
We can apply column operations and get boolean Series objects:
>>> df["B"] > 50
0 False
1 True
2 True
3 True
4 False
5...