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Stack vs heap allocation of structs in Go, and how they relate to garbage collection
...le stack-based programming where automatic variables live on the stack and allocated memory lives on the heap and and Python-style stack-based-programming where the only thing that lives on the stack are references/pointers to objects on the heap.
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Javascript reduce on array of objects
...eration 2: a = 3, b = {x:2} returns NaN
A number literal 3 does not (typically) have a property called x so it's undefined and undefined + b.x returns NaN and NaN + <anything> is always NaN
Clarification: I prefer my method over the other top answer in this thread as I disagree with the ide...
Subprocess changing directory
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@The_Diver That's why cd must be implemented as internal shell command. There's no other way to do it. Internal shell commands are executed within the same process as the shell. What I meant by subshell is the shell executed for ...
Extracting specific columns from a data frame
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Using the dplyr package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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Make an existing Git branch track a remote branch?
... 1.7.0 (before 1.8.0):
git branch --set-upstream foo upstream/foo
Notes:
All of the above commands will cause local branch foo to track remote branch foo from remote upstream.
The old (1.7.x) syntax is deprecated in favor of the new (1.8+) syntax. The new syntax is intended to be more intuitive a...
Case insensitive searching in Oracle
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Since 10gR2, Oracle allows to fine-tune the behaviour of string comparisons by setting the NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', ...
Tracking the script execution time in PHP
...";
echo "It spent " . rutime($ru, $rustart, "stime") .
" ms in system calls\n";
Note that you don't need to calculate a difference if you are spawning a php instance for every test.
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im...
Find out how much memory is being used by an object in Python [duplicate]
...and internal structures related to object types and garbage collection. Finally, some python objects have non-obvious behaviors. For instance, lists reserve space for more objects than they have, most of the time; dicts are even more complicated since they can operate in different ways (they have a ...
When would you use the different git merge strategies?
...s:
Recursive
Recursive is the default for non-fast-forward merges. We're all familiar with that one.
Octopus
I've used octopus when I've had several trees that needed to be merged. You see this in larger projects where many branches have had independent development and it's all ready to come to...
Accept function as parameter in PHP
... to find some documentation to link to first, and didn't know what it was called exactly. Ah well, now I'll know for when I need to do this as well. Thanks.
– Rob
Apr 23 '10 at 17:01
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