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append new row to old csv file python
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Are you opening the file with mode of 'a' instead of 'w'?
See Reading and Writing Files in the python docs
7.2. Reading and Writing Files
open() returns a file object, and is most commonly used with two arguments: open(filename, mode).
>>> f = open('workfile', 'w')
>>>...
For homebrew mysql installs, where's my.cnf?
...lp and look through it for the conf locations listed.
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/etc/my.cnf ~/.my.cnf
The following groups are read: mysql client
The following options may be given as the first argument:
--print-defaults...
How to read the mode field of git-ls-tree's output
... mask for file owner permissions
S_IRUSR 00400 owner has read permission
S_IWUSR 00200 owner has write permission
S_IXUSR 00100 owner has execute permission
S_IRWXG 00070 mask for group permissions
S_IRGRP 00040 group has read...
Boolean method naming readability
Simple question, from a readability standpoint, which method name do you prefer for a boolean method:
12 Answers
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Why does an SSH remote command get fewer environment variables then when run manually? [closed]
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startup files. If any of the files exist but cannot be
read, bash reports an error. Tildes are expanded in file
names as described below under Tilde Expansion in the
EXPANSION section.
When bash is invoked as an interactive login shell, or as
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How Scalable is SQLite? [closed]
I recently read this Question about SQLite vs MySQL and the answer pointed out that SQLite doesn't scale well and the official website sort-of confirms this , however.
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How to change string into QString?
...tr);
If you have const char * encoded with system encoding that can be read with QTextCodec::codecForLocale() then you should use this method:
QString QString::fromLocal8Bit(const char * str, int size = -1)
const char* str = "zażółć gęślą jaźń"; // latin2 source file and system e...
python pandas remove duplicate columns
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It sounds like you already know the unique column names. If that's the case, then df = df['Time', 'Time Relative', 'N2'] would work.
If not, your solution should work:
In [101]: vals = np.random.randint(0,20, (4,3))
vals
Out[101]:
arr...
Git Blame Commit Statistics
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git ls-tree -r HEAD|sed -re 's/^.{53}//'|while read filename; do file "$filename"; done|grep -E ': .*text'|sed -r -e 's/: .*//'|while read filename; do git blame -w "$filename"; done|sed -r -e 's/.*\((.*)[0-9]{4}-[0-9]{2}-[0-9]{2} .*/\1/' -e 's/ +$//'|sort|uniq -c
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what is the difference between const_iterator and iterator? [duplicate]
...rence regarding performance?
I guess when we are traversing the vector in "read only wise", we prefer const_iterator , right?
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