I have set of value in float (always less than 0). Which I want to bin into histogram,
i,e. each bar in histogram contain range of value [0,0.150)

The data I have looks like this:

0.000
0.005
0.124
0.000
0.004
0.000
0.111
0.112


Whith my code below I expect to get result that looks like

[0, 0.005) 5
[0.005, 0.011) 0
...etc..


I tried to do do such binning with this code of mine.
But it doesn't seem to work. What's the right way to do it?

#! /usr/bin/env python


import fileinput, math

log2 = math.log(2)

def getBin(x):
    return int(math.log(x+1)/log2)

diffCounts = [0] * 5

for line in fileinput.input():
    words = line.split()
    diff = float(words[0]) * 1000;

    diffCounts[ str(getBin(diff)) ] += 1

maxdiff = [i for i, c in enumerate(diffCounts) if c &gt; 0][-1]
print maxdiff
maxBin = max(maxdiff)


for i in range(maxBin+1):
     lo = 2**i - 1
     hi = 2**(i+1) - 1
     binStr = '[' + str(lo) + ',' + str(hi) + ')'
     print binStr + '\t' + '\t'.join(map(str, (diffCounts[i])))


~                                                                   


Question: Create connection string for MS-Access dynamically
Answer: Use Path.Combine and a OleDbConnectionStringBuilder to create a valid connection-string:

var conString = string.Format("Provider=Microsoft.Jet.OLEDB.4.0; Data Source={0}"
                             , Path.Combine(dir, "nik.mdb"));
var conBuilder = new OleDbConnectionStringBuilder(conString);
using (var con = new OleDbConnection(conBuilder.ConnectionString))
{
    // ...
}


Maybe you have white-spaces in the connection string.

Update Since you've edited your question and provided your connection-string. There is  a white-space between OLEDB.4.0; and Data. That might be  a possible reason for your exception. Then the ConnectionStringBuilder helps.