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How to write to file in Ruby?
I need to read the data out of database and then save it in a text file.
7 Answers
7
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python pandas remove duplicate columns
...
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...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...d, static array of characters,
and this unnamed array may be stored
in read-only memory, and which
therefore cannot necessarily be
modified. In an expression context,
the array is converted at once to a
pointer, as usual (see section 6), so
the second declaration initializes p
to poi...
Why use Ruby's attr_accessor, attr_reader and attr_writer?
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You may use the different accessors to communicate your intent to someone reading your code, and make it easier to write classes which will work correctly no matter how their public API is called.
class Person
attr_accessor :age
...
end
Here, I can see that I may both read and write the age....
Local Storage vs Cookies
...kies and local storage serve different purposes. Cookies are primarily for reading server-side, local storage can only be read by the client-side. So the question is, in your app, who needs this data — the client or the server?
If it's your client (your JavaScript), then by all means switch. You'...
Python import csv to list
...g the csv module:
import csv
with open('file.csv', newline='') as f:
reader = csv.reader(f)
data = list(reader)
print(data)
Output:
[['This is the first line', 'Line1'], ['This is the second line', 'Line2'], ['This is the third line', 'Line3']]
If you need tuples:
import csv
with...
'Incomplete final line' warning when trying to read a .csv file into R
I'm trying to read a .csv file into R and upon using this formula:
15 Answers
15
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How to know what the 'errno' means?
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You can use strerror() to get a human-readable string for the error number. This is the same string printed by perror() but it's useful if you're formatting the error message for something other than standard error output.
For example:
#include <errno.h>
...
How to get the device's IMEI/ESN programmatically in android?
...AndroidManifest.xml:
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
in order to do this.
That being said, be careful about doing this. Not only will users wonder why your application is accessing their telephony stack, it might be difficult to migrate data over if t...
Confused about stdin, stdout and stderr?
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Standard input - this is the file handle that your process reads to get information from you.
Standard output - your process writes normal information to this file handle.
Standard error - your process writes error information to this file handle.
That's about as dumbed-down as I ...