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Case preserving substitute in Vim
...toMark Lodato
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16
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Understanding slice notation
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answered Feb 3 '09 at 22:48
Greg HewgillGreg Hewgill
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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
How to read a .xlsx file using the pandas Library in iPython?
... for sheet_name in xl_file.sheet_names}
Update: In pandas version 0.21.0+ you will get this behavior more cleanly by passing sheet_name=None to read_excel:
dfs = pd.read_excel(file_name, sheet_name=None)
In 0.20 and prior, this was sheetname rather than sheet_name (this is now deprecat...
Insert a row to pandas dataframe
...df.sort_index() # sorting by index
And you get, as desired:
A B C
0 2 3 4
1 5 6 7
2 7 8 9
See in Pandas documentation Indexing: Setting with enlargement.
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How to create custom easing function with Core Animation?
...tric.h:
// this should be a function that takes a time value between
// 0.0 and 1.0 (where 0.0 is the beginning of the animation
// and 1.0 is the end) and returns a scale factor where 0.0
// would produce the starting value and 1.0 would produce the
// ending value
typedef double (^KeyframePa...
Is SQL or even TSQL Turing Complete?
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Qantas 94 Heavy
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answered Sep 28 '11 at 7:59
Jan de VosJan de Vos
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Programmatically create a UIView with color gradient
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702
Objective-C:
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 50)];
CAGradie...
How to compare strings ignoring the case
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You're looking for casecmp. It returns 0 if two strings are equal, case-insensitively.
str1.casecmp(str2) == 0
"Apple".casecmp("APPLE") == 0
#=> true
Alternatively, you can convert both strings to lower case (str.downcase) and compare for equality.
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Removing trailing newline character from fgets() input
... ugly way:
char *pos;
if ((pos=strchr(Name, '\n')) != NULL)
*pos = '\0';
else
/* input too long for buffer, flag error */
The slightly strange way:
strtok(Name, "\n");
Note that the strtok function doesn't work as expected if the user enters an empty string (i.e. presses only Enter). ...