#=========================================================================
# NAME: read_array_demo1
#
# DESCRIPTION: Examples to read 2 columns from a multicolumn ascii text
# file, skipping the first line of header. First example reads into
# 2 separate arrays. Second example reads into a single array. Data are
# then plotted.
#
# Here is the format of the file test.txt:
# --------
# Some header to skip
# 1 2 3
# 2 4 6
# 3 6 9
# 4 8 12
#
# USAGE:
# python read_array_demo1.py
#
# PARAMETERS:
#
# DEPENDENCIES:
# matplotlib (pylab)
# test.txt
#
#
# AUTHOR: Simon J. Hook
# DATE : 09/23/2005
#
# MODIFICATION HISTORY:
#
# COMMENT:
#
#============================================================================
from scipy import *
from scipy.io import read_array
from pylab import *
def main():
# First example, read first and second column from ascii file. Skip first
# line of header.
# Note use of (1,-1) in lines to skip first line and then read to end of file
# Note use of (0,) in columns to pick first column, since its a tuple need trailing comma
x=read_array("test.txt",lines=(1,-1), columns=(0,))
y=read_array("test.txt",lines=(1,-1), columns=(1,))
#Second example, read the file into a single arry
z=read_array("test.txt",lines=(1,-1), columns=(0,2))
# Plot the data
plot(x,y,'r--',z[:,0],z[:,1])
show()
# The one and only main function
if __name__ == "__main__":
main()
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