How to sort dataframe by value in Pandas?

Question

I have a data set in csv that I read with pd.read_csv. I want to sort the esxisting data by descanding value.

my code is this:

dataset = pd.read_csv('Kripto.csv')
sorted = dataset.sort_values(by = "Freq1", ascending=False)

x = dataset.iloc[:, :].values

and my data set (print(dataset)) is this :

 Letter;Freq1

0      A;0.0817

1      B;0.0150

2      C;0.0278

3      D;0.0425

4      E;0.1270

when i want to use this code:

sorted = dataset.sort_values(by = "Freq1", ascending=False)

python gives me an error and says KeyError: 'Freq1'

I know that "Freq1" is not the name of the column but ı have no idea how to assing a name

dataset = pd.read_csv('Kripto.csv', sep=';') would fix your problem. — Quang Hoang
– Quang Hoang, Commented Mar 29, 2021 at 0:26
Note that sorting is almost only useful for printing (that is, for humans); especially when you are working with dataframes, since selections are normally done on other criteria than the order. — 9769953
– 9769953, Commented Mar 29, 2021 at 0:31

Alfonso Murrieta · Accepted Answer · 2021-03-29 01:26:28Z

1

Your csv file has " ; " as separator, you need to indicate on the read_csv method:

import pandas as pd
dataset = pd.read_csv('your.csv', sep=';')

And that's all you need to do

answered Mar 29, 2021 at 1:26

Alfonso Murrieta

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Comments

9769953 · Accepted Answer · 2021-03-29 00:28:42Z

1

Your CSV file uses semi-colons to separate values. Since Pandas by defaults expects comma's, use

dataset = pd.read_csv('Kripto.csv', sep=';')

instead.

You should also use the sorted dataset to get your values in sorted order, instead of dataset, since the latter will remain unsorted:

x = sorted.iloc[:, :].values

answered Mar 29, 2021 at 0:28

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