Difference between io.open vs open in python

Situation in Python3 according to the docs: io.open(file, *[options]*) This is an alias for the builtin open() function. and While the builtin open() and the associated io module are the recommended approach for working with encoded text files, this module [i.e. codecs] provides additional utility functions and classes that allow the use of a wider … Read more

Reading a file character by character in C

There are a number of things wrong with your code: char *readFile(char *fileName) { FILE *file; char *code = malloc(1000 * sizeof(char)); file = fopen(fileName, “r”); do { *code++ = (char)fgetc(file); } while(*code != EOF); return code; } What if the file is greater than 1,000 bytes? You are increasing code each time you read … Read more

How do you open a file in C++?

You need to use an ifstream if you just want to read (use an ofstream to write, or an fstream for both). To open a file in text mode, do the following: ifstream in(“filename.ext”, ios_base::in); // the in flag is optional To open a file in binary mode, you just need to add the “binary” … Read more

How do you use StringIO in Python3?

when i write import StringIO it says there is no such module. From What’s New In Python 3.0: The StringIO and cStringIO modules are gone. Instead, import the io module and use io.StringIO or io.BytesIO for text and data respectively. . A possibly useful method of fixing some Python 2 code to also work in … Read more

Read a small random sample from a big CSV file into a Pandas data frame

Assuming no header in the CSV file: import pandas import random n = 1000000 #number of records in file s = 10000 #desired sample size filename = “data.txt” skip = sorted(random.sample(range(n),n-s)) df = pandas.read_csv(filename, skiprows=skip) would be better if read_csv had a keeprows, or if skiprows took a callback func instead of a list. With … Read more