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Change one value based on another value in pandas
... numpy as np
df = pd.DataFrame([['dog', 'hound', 5],
['cat', 'ragdoll', 1]],
columns=['animal', 'type', 'age'])
In[1]:
Out[1]:
animal type age
----------------------
0 dog hound 5
1 cat ragdoll 1
Below we are adding a new description co...
Why is enum class preferred over plain enum?
...
enum class Color { red, green, blue }; // enum class
enum Animal { dog, cat, bird, human }; // plain enum
What is the difference between the two?
enum classes - enumerator names are local to the enum and their values do not implicitly convert to other types (like another enum or int)
Plain en...
how to check the dtype of a column in python pandas
...has existed since Pandas 0.13, and it does the same thing, but it was deprecated in favour of pandas.api.types.is_numeric_dtype in 0.19, I think
– Migwell
May 8 '19 at 0:50
...
Longest line in a file
...
Why the extra cat command? Just give the file name directly as an argument to awk.
– Thomas Padron-McCarthy
Oct 31 '09 at 21:40
...
Maximum number of threads per process in Linux?
...esses with a shared address space on Linux) which you can view like this:
cat /proc/sys/kernel/threads-max
The default is the number of memory pages/4. You can increase this like:
echo 100000 > /proc/sys/kernel/threads-max
There is also a limit on the number of processes (and hence threads...
Use of *args and **kwargs [duplicate]
... c = {2}'.format(a,b,c))
...
>>> mylist = ['aardvark', 'baboon', 'cat']
>>> print_three_things(*mylist)
a = aardvark, b = baboon, c = cat
As you can see in this case it takes the list (or tuple) of items and unpacks it. By this it matches them to the arguments in the function. O...
Unable to Cast from Parent Class to Child Class
...ity. I did that so I didn't have to import the web reference into my application since it was in my helper library. This allowed me to convert the parent to my wrapper class. Thank you!
– BrianVPS
Nov 17 '17 at 1:30
...
常用Linux命令详解（持续更新） - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的 “data*” 文件？
三、文本操作
1. 显示文本内容的cat命令
cat(concatenate) 命令可以显示文件的内容(经常和more命令搭配使用)，或是将数个文件合并成一个文件。范例如下:
逐页显示 file.txt的内容:
[root@KEDACOM temp]# cat file.txt...
Java - escape string to prevent SQL injection
...y {
try {
if (stmt != null) { stmt.close(); }
}
catch (Exception e) {
// log this error
}
try {
if (conn != null) { conn.close(); }
}
catch (Exception e) {
// log this error
}
}
}
No matter what characters are i...
Why is there no SortedList in Java?
...thermore if you are sure that you don't need to worry about (or have) duplicate elements then you can use the TreeSet<T> instead. It implements SortedSet and NavigableSet interfaces and works as you'd probably expect from a list:
TreeSet<String> set = new TreeSet<String>();
set.ad...