大约有 2,400 项符合查询结果（耗时：0.0231秒） [XML]
How to estimate how much memory a Pandas' DataFrame will need?
I have been wondering... If I am reading, say, a 400MB csv file into a pandas dataframe (using read_csv or read_table), is there any way to guesstimate how much memory this will need? Just trying to get a better feel of data frames and memory...
...
Can iterators be reset in Python?
...y available.
As several answers rightly remarked, in the specific case of csv you can also .seek(0) the underlying file object (a rather special case). I'm not sure that's documented and guaranteed, though it does currently work; it would probably be worth considering only for truly huge csv file...
Create Pandas DataFrame from a string
...ringIO (python2) or io.StringIO (python3) and pass that to the pandas.read_csv function. E.g:
import sys
if sys.version_info[0] < 3:
from StringIO import StringIO
else:
from io import StringIO
import pandas as pd
TESTDATA = StringIO("""col1;col2;col3
1;4.4;99
2;4.5;200
3;4...
Load data from txt with pandas
...
You can use:
data = pd.read_csv('output_list.txt', sep=" ", header=None)
data.columns = ["a", "b", "c", "etc."]
Add sep=" " in your code, leaving a blank space between the quotes. So pandas can detect spaces between values and sort in columns. Data co...
Open the file in universal-newline mode using the CSV Django module
I am trying to access a model.filefield in Django to parse a CSV file in Python using the csv module. It's working on Windows, but on Mac it gave me this:
...
Trimming a huge (3.5 GB) csv file to read into R
...
My try with readLines. This piece of a code creates csv with selected years.
file_in <- file("in.csv","r")
file_out <- file("out.csv","a")
x <- readLines(file_in, n=1)
writeLines(x, file_out) # copy headers
B <- 300000 # depends how large is one pack
while(length...
Specify custom Date format for colClasses argument in read.table/read.csv
...cify the Date format when using the colClasses argument in read.table/read.csv?
4 Answers
...
How is Pythons glob.glob ordered?
...:
My files were returned by glob something like:
myList = ["c:\tmp\x\123.csv", "c:\tmp\x\44.csv", "c:\tmp\x\101.csv", "c:\tmp\x\102.csv", "c:\tmp\x\12.csv"]
I sorted the list in place, to do this I created a function:
def sortKeyFunc(s):
return int(os.path.basename(s)[:-4])
This function ...
c# datatable to csv
...tell me why the following code is not working. The data is saved into the csv file, however the data is not separated. It all exists within the first cell of each row.
...
Alternative for PHP_excel
...ta by Eli Dickinson (Writes SpreadsheetML - the Excel 2003 XML format, and CSV)
Oliver Schwarz's php-excel (SpreadsheetML)
Oliver Schwarz's original version of php-excel (SpreadsheetML)
excel_xml (SpreadsheetML, despite its name)... link reported as broken
The tiny-but-strong (tbs) project includes ...