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How do you see the entire command history in interactive Python?
...OS X, and I Cmd + K (cleared) my earlier commands. I can go through them one by one using the arrow keys. But is there an option like the --history option in bash shell, which shows you all the commands you've entered so far?
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How to rename a single column in a data.frame?
...ewname2"
attempts to set the second column's name. Your object only has one column, so the command throws an error. This should be sufficient:
colnames(trSamp) <- "newname2"
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Django admin: how to sort by one of the custom list_display fields that has no database field
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This is better answer compared to the accepted one. The issue I ran into applying the accepted one is when you search something along with that updated queryset at the admin level, it takes too much time and also comes up with wrong count for the results it found.
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Numpy where function multiple conditions
...t way in your particular case would just be to change your two criteria to one criterion:
dists[abs(dists - r - dr/2.) <= dr/2.]
It only creates one boolean array, and in my opinion is easier to read because it says, is dist within a dr or r? (Though I'd redefine r to be the center of your reg...
How to think in data stores instead of databases?
...arates it from RDMBS. to scale better with large dataset, App Engine has done some changes(some means lot of changes).
RDBMS VS DataStore
Structure
In database, we usually structure our data in Tables, Rows which is in Datastore it becomes Kinds and Entities.
Relations
In RDBMS, Most of the peop...
What's the point of OOP?
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@melaos: the summary is in the middle. OOP is one tool in the toolkit, not the only one, and there is no substitute for training, experience, and judgement.
– Mike Dunlavey
Dec 31 '08 at 14:37
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Why does only the first line of this Windows batch file execute but all three lines execute in a com
I have a batch file that executes three Maven commands, one after the other. Each command can be successfully executed in the script - by itself!. But when I add all three commands to the same file, only the first one executes before the script exits. Any idea why?
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Visual Studio warning: “Some of the properties associated with the solution could not be read”
When I open my solution, I get a dialog with this warning. The solution (one web app, one class project) builds without errors.
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How can one see content of stack with GDB?
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You need to use gdb's memory-display commands. The basic one is x, for examine. There's an example on the linked-to page that uses
gdb> x/4xw $sp
to print "four words (w ) of memory above the stack pointer (here, $sp) in hexadecimal (x)". The quotation is slightly paraphrased...
how to use “AND”, “OR” for RewriteCond on Apache?
...u'll quickly spot the defines used to name these flags:
#define CONDFLAG_NONE 1<<0
#define CONDFLAG_NOCASE 1<<1
#define CONDFLAG_NOTMATCH 1<<2
#define CONDFLAG_ORNEXT 1<<3
#define CONDFLAG_NOVARY 1<<4
and se...