From b68c69be4385e2a2dbd9e897d317f117fbf5d071 Mon Sep 17 00:00:00 2001
From: sloanlewis <38470406+sloanlewis@users.noreply.github.com>
Date: Mon, 21 Jan 2019 20:31:22 -0800
Subject: [PATCH] Add files via upload

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+#Lab 2
+##File processing in Python
+How do you ask if a file exists?
+
+```
+import os
+os.path.isfile('./file')
+```
+How to you ask if a file is a directory?
+
+```
+import os
+os.path.isdir('./dir')
+```
+How do you remove (delete) a file?
+
+```
+import os
+os.remove('./file')
+```
+How do you get the size of a file?
+
+```
+import os
+statinfo = os.stat('file')
+statinfo.st_size
+```
+How do you get all the file names matching a pattern?
+
+```
+import glob
+glob.glob('pattern')
+```
+How do you get all the file names matching a pattern recursively?
+
+```
+import glob
+glob.glob(/*/'pattern')
+```
+How do you get an iterator to all files matching a pattern, as opposed to returning a potentially huge list?
+
+```
+import glob
+glob.iglob('pattern')
+```
+How do you open gzip-compressed files for reading and for writing?
+
+_reading:_
+
+```
+import gzip
+with gzip.open('file.txt.gz', 'rb') as f:
+    file_content = f.read()
+```
+_writing:_
+
+```
+import gzip
+with gzip.open('file.txt.gz', 'wb') as f:
+    file_content = f.write()
+```
+
+
+##In R
+How do you ask if a file exists?
+
+```
+file.exists("file")
+```
+How to you ask if a file is a directory?
+
+```
+dir.exists("dir")
+```
+
+How do you remove (delete) a file?
+
+```
+file.remove("file")
+```
+How do you get the size of a file?
+
+```
+file.info("file")
+```
+
+How do you get all the file names matching a pattern?
+
+```
+list.files(pattern="pattern_you_want")
+```
+
+How do you get all the file names matching a pattern recursively?
+
+```
+list.files(pattern="pattern_you_want", recursive=TRUE)
+```
+
+How do you open gzip-compressed files for reading and for writing?
+
+```
+library(R.utils)
+gunzip("file.gz")
+```
+
+##Python
+
+```{py}
+import glob
+import os.path
+output=[]
+for file in glob.glob('./lab2data/*/*'):
+	base=os.path.basename(file)
+	rawfile=os.path.splitext(base)[0]
+	raw2=rawfile.split(".",1)[1]
+	for i in raw2:
+		output.append(raw2)
+myset = set(output)
+my_list = ['outfile.' + x + '.out' for x in myset]
+print(my_list)
+
+```
+
+##R
+
+```
+library(tidyverse)
+files <- list.files(recursive = TRUE, full.names = FALSE)
+files <- files %>%
+	gsub(., pattern = "data/datafile.", replacement = "") %>%
+	gsub(., pattern = "output/outfile.", replacement = '') %>%
+	gsub(., pattern = ".txt", replacement = "") %>%
+	gsub(., pattern = ".out", replacement = "") %>%
+unique_files <- unique(files)
+unique_files <- paste0("outfile.", unique_files, ".out")
+```