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Naming returned columns in Pandas aggregate function? [duplicate]
...er, this does not work with lambda functions, since they are anonymous and all return <lambda>, which causes a name collision:
>>> df.groupby('A').agg({'B': [lambda x: x.min(), lambda x: x.max]})
SpecificationError: Function names must be unique, found multiple named <lambda>
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Alternatives to gprof [closed]
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Valgrind has an instruction-count profiler with a very nice visualizer called KCacheGrind. As Mike Dunlavey recommends, Valgrind counts the fraction of instructions for which a procedure is live on the stack, although I'm sorry to say it appears to become confused in the presence of mutual recur...
Calculating a directory's size using Python?
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This walks all sub-directories; summing file sizes:
import os
def get_size(start_path = '.'):
total_size = 0
for dirpath, dirnames, filenames in os.walk(start_path):
for f in filenames:
fp = os.path.join(di...
How to avoid annoying error “declared and not used”
...s it easier to read code written by other people (you are always sure that all declared variables will be used), and avoid some possible dead code.
But, if you really want to skip this error, you can use the blank identifier (_) :
package main
import (
"fmt" // imported and not used: "fmt"
)
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How to save an HTML5 Canvas as an image on a server?
I'm working on a generative art project where I would like to allow users to save the resulting images from an algorithm. The general idea is:
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When do I use the PHP constant “PHP_EOL”?
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@Andre: How about anyone that writes apps to be installed, used and deployed by others? Are you suggesting these should all limit their "supported platforms" to *nix?
– Cylindric
Mar 4 '11 at 10:52
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Can I query MongoDB ObjectId by date?
...Seconds + "0000000000000000");
return constructedObjectId
}
/* Find all documents created after midnight on May 25th, 1980 */
db.mycollection.find({ _id: { $gt: objectIdWithTimestamp('1980/05/25') } });
share
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ORA-12514 TNS:listener does not currently know of service requested in connect descriptor
We have an application running locally where we're experiencing the following error:
25 Answers
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Twitter API returns error 215, Bad Authentication Data
I am trying to call following Twitter's API to get a list of followers for a user.
15 Answers
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Looking to understand the iOS UIViewController lifecycle
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All these commands are called automatically at the appropriate times by iOS when you load/present/hide the view controller. It's important to note that these methods are attached to UIViewController and not to UIViews themsel...