大约有 40,000 项符合查询结果（耗时：0.0348秒） [XML]
Abort makefile if variable not set
... an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defined,$...
Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
...
List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
...
With new_list = my_list, you don't actually have two lists. The assignment just copies the reference to the list, not the actual list, so both new_list and my_list refer to the same list after the assignment.
To actually copy the list, you have various possibilit...
How can I link to a specific glibc version?
... of Sun's symbol versioning scheme described here.
One option is to statically link your binary. This is probably the easiest option.
You could also build your binary in a chroot build environment, or using a glibc-new => glibc-old cross-compiler.
According to the http://www.trevorpounds.com...
What does the brk() system call do?
...d load the "text" and "data" blocks into RAM starting at address zero (actually a little above address zero, so that the NULL pointer genuinely didn't point to anything) and set the break address to the end of the data segment. The first call to malloc would then use sbrk to move the break up and c...
What is the type of lambda when deduced with “auto” in C++11?
...
The type of a lambda expression is unspecified.
But they are generally mere syntactic sugar for functors. A lambda is translated directly into a functor. Anything inside the [] are turned into constructor parameters and members of the functor object, and the parameters inside () are turned ...
How to convert ActiveRecord results into an array of hashes
...d objects to Ruby Hashes despite its name
tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json
# You can now add new records and return the result as json by calling `to_json`
tasks_records << TaskStoreStatus.last.as_json
tasks_records << { :task_id => 10, :sto...
How do I choose grid and block dimensions for CUDA kernels?
...eads per block should be a round multiple of the warp size, which is 32 on all current hardware.
Each streaming multiprocessor unit on the GPU must have enough active warps to sufficiently hide all of the different memory and instruction pipeline latency of the architecture and achieve maximum throu...
How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
Is there a “goto” statement in bash?
...atement in bash ? I know It is considered bad practice, but I need specifically "goto".
12 Answers
...