substituting in a file
<p>I use python 2.5, i like to replace certain variables in a txt file and write the complete data into new file.</p>

<p>i wrote a program to do the above,</p>

<pre><code>from scipy import *

import numpy 

from numpy import asarray

from string import Template


def Dat(Par):


 Par = numpy.asarray(Par)

 Par[0] = a1

 Par[1] = a2

 Par[2] = a3

 Par[3] = a4

 sTemplate=Template(open('/home/av/W/python/data.txt', 'r').read()).safe_substitute(Par)

 open('/home/av/W/python/data_new.txt' ,'w').write(sTemplate)


Init = numpy.asarray [(10.0, 200.0, 500.0, 10.0)]

Dat(Init)
</code></pre>

<p>when i executed the above 
*i obtained the error </p>

<pre><code>'TypeError: 'function' object is unsubscriptable'
</code></pre>

<p>'data.txt' is a text file, i have placed $a1, $a2, $a3, $a4, i need to replace $a1  $a2  $a3  $a4 by 10.0  200.0  500.0  10.0</p>

<p>My constraints are i need to pass the values only by array like Init = numpy.asarray [(10.0, 200.0, 500.0, 10.0)] </p>

<p>please help me.</p>

<p>is this error due to python 2.5 version? or any mistakes in program</p>
