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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...
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On design patterns: When should I use the singleton?
The glorified global variable - becomes a gloried global class. Some say breaking object-oriented design.
19 Answers
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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...
csv文件用excel打开修改保存后,日期少了秒 - 更多技术 - 清泛网 - 专注C/C++及内核技术
csv文件用excel打开修改保存后,日期少了秒csv格式的日期打开默认是没有秒的，而且再次保存后秒回丢失，通过设置单元格自定义类型可以解决。选中单元格（或选中列）右键，设置单元格...csv格式的日期打开默认是没有秒的，而...
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
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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:
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Trimming a huge (3.5 GB) csv file to read into R
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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...
How can I override Bootstrap CSS styles?
...Dec 21 '13 at 17:04
Markus KottländerMarkus Kottländer
7,41033 gold badges3131 silver badges5757 bronze badges
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Equals(=) vs. LIKE
...duce results different from the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLATE latin1_german2_ci;
+-----------------------------------------+
| 'ä' LIKE 'ae' COLLATE latin1_german2_ci |
+-----------------------------------------+
| 0 |
+------...