Importing Data into Python.ipynb

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    "#################  IMPORTING TEXT FILES\n",
    "# Open a file: file\n",
    "file = open('moby_dick.txt', 'r')\n",
    "# Print it\n",
    "print(file.read())\n",
    "# Check whether file is closed\n",
    "print(file.close())\n",
    "# Close file\n",
    "file.close()\n",
    "# Check whether file is closed\n",
    "print(file.closed)\n",
    "\n",
    "############### READING FILES LINE BY LINE\n",
    "# Read & print the first 3 lines\n",
    "with open('moby_dick.txt') as file:\n",
    "    print(file.readline())\n",
    "    print(file.readline())\n",
    "    print(file.readline())\n",
    "\n",
    "    \n",
    "############### USING NUMPY FOR FLAT FILES\n",
    "# Import package\n",
    "import numpy as np\n",
    "# Assign filename to variable: file\n",
    "file = 'digits.csv'\n",
    "# Load file as array: digits\n",
    "digits = np.loadtxt(file, delimiter=',')\n",
    "# Print datatype of digits\n",
    "print(digits)\n",
    "# Select and reshape a row\n",
    "im = digits[21, 1:]\n",
    "im_sq = np.reshape(im, (28, 28))\n",
    "# Plot reshaped data (matplotlib.pyplot already loaded as plt)\n",
    "plt.imshow(im_sq, cmap='Greys', interpolation='nearest')\n",
    "plt.show()\n",
    "\n",
    "\n",
    "############### LOADING FILE WITH DELIMITER\n",
    "# Import package\n",
    "import numpy as np\n",
    "# Assign filename to variable: file\n",
    "file = 'digits.csv'\n",
    "# Load file as array: digits\n",
    "digits = np.loadtxt(file, delimiter=',')\n",
    "# Print datatype of digits\n",
    "print(type(digits))\n",
    "# Select and reshape a row\n",
    "im = digits[21, 1:]\n",
    "im_sq = np.reshape(im, (28, 28))\n",
    "# Plot reshaped data (matplotlib.pyplot already loaded as plt)\n",
    "plt.imshow(im_sq, cmap='Greys', interpolation='nearest')\n",
    "plt.show()\n",
    "\n",
    "############### CUSTOMIZING NUMPY IMPORTS\n",
    "# Import numpy\n",
    "import numpy as np\n",
    "# Assign the filename: file\n",
    "file = 'digits_header.txt'\n",
    "# Load the data: data\n",
    "data = np.loadtxt(file, delimiter='\\t', skiprows=1, usecols=[0,2])\n",
    "# Print data\n",
    "print(data)\n",
    "\n",
    "\n",
    "############## IMPORTING DIFFERING DATA TYPES\n",
    "# Assign filename: file\n",
    "file = 'seaslug.txt'\n",
    "# Import file: data\n",
    "data = np.loadtxt(file, delimiter='\\t', dtype=str)\n",
    "# Print the first element of data\n",
    "print(data[0])\n",
    "# Import data as floats and skip the first row: data_float\n",
    "data_float = np.loadtxt(file, delimiter='\\t', dtype=float, skiprows=1)   #<------header was skipped\n",
    "# Print the 10th element of data_float\n",
    "print(data_float[9])\n",
    "# Plot a scatterplot of the data\n",
    "plt.scatter(data_float[:, 0], data_float[:, 1])\n",
    "plt.xlabel('time (min.)')\n",
    "plt.ylabel('percentage of larvae')\n",
    "plt.show()\n",
    "\n",
    "# Assign the filename: file\n",
    "file = 'titanic.csv'\n",
    "# Import file using np.recfromcsv: d\n",
    "d = np.recfromcsv(file)\n",
    "# Print out first three entries of d\n",
    "print(d[:3])"
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    "##################  USING PANDAS TO IMPORT CSV\n",
    "# Import pandas as pd\n",
    "import pandas as pd\n",
    "# Assign the filename: file\n",
    "file = 'titanic.csv'\n",
    "# Read the file into a DataFrame: df\n",
    "df = pd.read_csv(file)\n",
    "# View the head of the DataFrame\n",
    "df.head()\n",
    "\n",
    "# Assign the filename: file\n",
    "file = 'digits.csv'\n",
    "# Read the first 5 rows of the file into a DataFrame: data\n",
    "data = pd.read_csv(file,nrows=5,header=None)\n",
    "# Build a numpy array from the DataFrame: data_array\n",
    "data_array=data.values\n",
    "# Print the datatype of data_array to the shell\n",
    "print(type(data_array))\n",
    "\n",
    "################  CUSTOMIZING PANDAS IMPORT\n",
    "# Import matplotlib.pyplot as plt\n",
    "import matplotlib.pyplot as plt\n",
    "# Assign filename: file\n",
    "file = 'titanic_corrupt.txt'\n",
    "# Import file: data\n",
    "data = pd.read_csv(file, sep='\\t', comment='#', na_values='Nothing')\n",
    "# Print the head of the DataFrame\n",
    "print(data.head())\n",
    "# Plot 'Age' variable in a histogram\n",
    "pd.DataFrame.hist(data[['Age']])\n",
    "plt.xlabel('Age (years)')\n",
    "plt.ylabel('count')\n",
    "plt.show()"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
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    "################ LOADING PICKLED FILES\n",
    "# Import pickle package\n",
    "import pickle\n",
    "# Open pickle file and load data: d\n",
    "with open('data.pkl', 'rb') as file:  #<----rb means read only and binary\n",
    "    d = pickle.load(file)\n",
    "# Print d\n",
    "print(d)\n",
    "# Print datatype of d\n",
    "print(type(d))\n",
    "\n",
    "\n",
    "################ LISTING SHEETS IN EXCEL\n",
    "# Import pandas\n",
    "import pandas as pd\n",
    "# Assign spreadsheet filename: file\n",
    "file = 'battledeath.xlsx'\n",
    "# Load spreadsheet: xl\n",
    "xl = pd.ExcelFile(file)\n",
    "# Print sheet names\n",
    "print(xl.sheet_names)\n"
   ]
  }
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